It’s excruciatingly awkward when you run into your ex. With that said, can you imagine working with your ex right after breaking up? Celebrities often form a romantic relationship with their co-stars. They meet on the set of a TV show or film and fall in love. We love it when that happens, but unfortunately, most of the times, they break up while filming. No matter how their split went, celebrities have to maintain their dignity and put up a facade because, at the end of the day, the show must go on.

Breakups are hard. We don’t know how celebrities do it, but they manage to work with their exes. They have to see their ex on set every day for months or even longer, and that can be hard on the heart. It’s even harder when their characters have an on-screen romance, and they have to continue with their fictional love life — be lovey-dovey with each other and even film intimate scenes when their off-screen romance went south. Talk about professionalism. Overall, mixing business with pleasure can be a bad thing.

Here’s the list of 17 celebrities who had to continue working with their exes. If that’s not awkward, then what is?

17 Jennifer Lawrence & Nicholas Hoult: They Mixed Business With Pleasure When They First Met While Filming For 'X-Men'

Jennifer Lawrence and Nicholas Hoult started dating in 2010 after they met on the set of X-Men: First Class. The couple broke up in January 2013, but they rekindled their romance a few months later when they reunited to film X-Men: Days of Future Past. Sadly, they ended their relationship for good in August 2014. An insider told E! News,

"They spent a lot of time apart because of work, and it was difficult on their relationship."

Even though their split was "very amicable," it was probably still awkward for them to work together on X-Men: Apocalypse. Also, that wasn't the last time — the exes got together again for work. They reprised their roles as Mystique and Beast for X-Men: Dark Phoenix, which is set to be released next year.

16 Blake Lively & Penn Badgley: Serena And Dan Got Married To Each Other In 'Gossip Girl's Series Finale

Blake Lively and Penn Badgley met on the set of Gossip Girl in 2007, and they dated for three years before breaking up in 2010. They kept their breakup a secret and were professional on set. Gossip Girl’s executive producer Joshua Safran told Vanity Fair, “The shocking thing was, I found out on the set of the Season Two finale that Blake and Penn had broken up months before.” In 2015, Penn appeared on Watch What Happens Live and revealed his best and worst on-screen kiss. He said, “I’d say best… I’ll say it was Blake because we actually had a relationship at the time. And worst? Maybe Blake after we broke up." It didn’t work out for the co-stars, but their characters, Serena van der Woodsen and Dan Humphrey, get married in the series finale.

15 Kristen Stewart & Robert Pattinson: Edward And Bella Had Better Chemistry In 'Twilight' Than Their Real-Life Romance

The co-stars met while filming the first Twilight movie in 2008. There were constant rumors about them dating, and their relationship was confirmed in 2010. Many Twilight fans were thrilled when Kristen Stewart and Robert Pattinson took their on-screen romance off-screen. Unfortunately, they broke up when Kristen was caught being unfaithful. In July 2012, Us Weekly published intimate photos of her and her Snow White and the Huntsman’s director, Rupert Sanders. Because the affair happened after the Twilight franchise's last film wrapped up, Kristen and Robert didn't have to continue with their fictional love life.

However, they had to reunite for press tours to promote Breaking Dawn Part 2.

They tried to work things out, but apparently, Robert couldn’t trust her anymore, and they called it quits in May 2013.

14 Nina Dobrev & Ian Somerhalder: Elena Ended Up With Damon On 'The Vampire Diaries' Final Season

Nina Dobrev and Ian Somerhalder were #relationshipgoals. They met on the set of The Vampire Diaries in 2009, and they were friends before they started dating in 2010. Fans were so overjoyed when they took their romance off-screen, because their characters, Elena Gilbert and Damon Salvatore, have intense chemistry on-screen. The couple dated for three years before breaking up in May 2013. They maintained a professional relationship and even filmed intimate scenes together until Nina left after season six in 2015. The exes spent two years romancing each other on-screen, and that probably wasn't comfortable for either of them. Nina reprised her role as Elena for the show’s final season. Nina and Ian didn’t get their happily-ever-after, but at least their characters end up together in the series finale.

13 Kaley Cuoco & Johnny Galecki: Penny And Leonard Continue To Have An Adorable Relationship On 'The Big Bang Theory'

Kaley Cuoco and Johnny Galecki have been with The Big Bang Theory since 2007. Their characters, Penny and Leonard, had an on-again, off-again relationship throughout the series. The co-stars also dated in real life but kept their relationship under the radar. Kaley told CBS Watch! Magazine in 2010 —

"We dated for almost two years. It was such a huge part of my life and no one knew about it."

"This is the first time I've ever talked about it, ever. It was a wonderful relationship, but we never spoke a word about it and never went anywhere together." They broke up in 2009 and kept it professional on set. It probably wasn’t easy for them to be lovey-dovey. The show is currently in its 11th season, and the exes play on-screen husband and wife.

12 Rachel Bilson & Adam Brody: Summer And Seth Had Their Happily Ever After On 'The O.C.'

Adorable couple on The O.C. — Summer Roberts and Seth Cohen — became a couple in real life. They dated in 2003 while filming for the series. Summer was only supposed to appear in a few episodes, but creator Josh Schwartz made her a series regular. It could be because she and Seth have intense chemistry on-screen. After all, Rachel Bilson and Adam Brody were dating off-screen. The couple broke up in 2006 after three years together. The O.C. ended in 2007, so they had to work together for another year. Not only did they have to act like they're in love, but they also had to film their wedding for the series finale. Well, that’s awkward. Rachel and Adam found love with other actors, but Summer and Seth live happily ever after.

11 Jennifer Carpenter & Michael C. Hall: The Former Couple Divorced Two Years Before 'Dexter' Ended

Many celebrities fall in love on set, and that's what happened with Jennifer Carpenter and Michael C. Hall. They met on the set of Dexter in 2006. After dating for a year and a half, the couple eloped on New Year's Eve in 2008. Two years after their marriage, they filed for divorce in 2010. Their divorce was finalized in 2011.

There were rumors that Julia Stiles, who plays Dexter’s love interest on the show, was the cause of their divorce.

However, Julia told Us Weekly, "I have absolutely nothing to do with the split between Michael and Jennifer. We are good friends and enjoyed working together.” Whatever the reason behind their divorce was, the exes maintained a professional relationship and continued to work together as co-stars until the series ended in 2013.

10 Crystal Reed & Daniel Sharman: They Kept Going With Their Steamy On-Screen Romance In 'Teen Wolf'

Teen Wolf co-stars, Crystal Reed and Daniel Sharman formed a romantic relationship in real life during the show’s second season in 2012. The couple parted ways in 2013. Post-breakup, Crystal went to Paris. She told Us Weekly, "I went by myself and it was cold, but it was still really, really beautiful. I was just getting over a breakup, so it was something that just jumpstarted my singleness.” She later appeared on Fashion Police where she revealed that she and her ex-boyfriend had to film a steamy scene together. She said, "We just started filming yesterday, and our very first scene was a [kissing] scene." Awkward much? Crystal and Daniel's characters started to have an on-screen romance while they were dating, but unfortunately, the romance went on even after their breakup.

9 Katie Holmes & Joshua Jackson: Joey And Pacey's Relationship Lasted Much Longer On 'Dawson's Creek'

Dawson’s Creek is known for its love triangle between three best friends — Dawson, Joey, and Pacey. Joey ultimately chooses Pacey, and their relationship lasted much longer than their real-life romance. The relationship between Katie Holmes and Joshua Jackson blossomed off-screen as well. They briefly dated while filming the show’s first season.

Katie revealed that Joshua's her first love.

She told Rolling Stones, "I'm just going to say that I met somebody last year, I fell in love, I had my first love, and it was something so incredible and indescribable.” They broke up early on in their relationship, and they had to work together for a few years until the series finale. Even if they ended on good terms and became friends, it was probably still uncomfortable to film affectionate scenes together.

8 Sophia Bush & Chad Michael Murray: They Each Became Romantically Involved With Other 'One Tree Hill' Co-Stars

Sophia Bush and Chad Michael Murray met on the set of One Tree Hill in 2003. The co-stars fell head over heels for each other and tied the knot in 2005 after dating for two years. Things didn’t work out, and Sophia filed for annulment five months later. Their divorce was finalized in 2006. However, the exes were forced to work together for three years until Chad left the series in 2009. They maintained a professional relationship and continued to play their on-screen characters, Brooke and Lucas. That must have been tough and awkward — acting like they're a couple in love after their highly-publicized split. It's interesting that their characters also end their relationship. Sophia and Chad put their divorce behind them, and they each dated other One Tree Hill co-stars.

7 Gwen Stefani & Tony Kanal: No Doubt Almost Broke Up But Instead Released A Breakup Song "Don't Speak"

No Doubt’s bassist Tony Kanal was Gwen Stefani’s first boyfriend. She was so heartbroken when he ended their relationship in 1994 after dating for seven years. It inspired her to write the hit song, “Don’t Speak." Gwen said on The Howard Stern Show in 2016,

“I was in love and obsessed with Tony Kanal, and he knows that.”

According to E News, Gwen would have married Tony and had kids with him if he would have asked. Tony also had a hard time with the breakup. He told The Guardian, "We were on tour for Tragic Kingdom for 28 months. We were going through the breakup, and in every interview, we were talking about it so we were opening this wound on an hourly basis. It was so brutal but I don't know how we made it through."

6 Cameron Diaz & Justin Timberlake: The Exes Filmed The Most Awkward Scene Together In 'Bad Teacher'

Cameron Diaz and Justin Timberlake met at Nickelodeon's Kid's Choice Awards in April 2003. They called it quits in 2007 after dating for almost four years, and apparently, Scarlet Johansson was the cause of their split. Cameron and Justin moved on and dated other people, but in 2011, former flames reunited to film Bad Teacher. Most ex-lovers would try to avoid working together, but they were mature about it and agreed to be in the same film. Exes can be friends, but wouldn't it still be awkward to film a love scene together? The scene was supposed to be funny, but it was weird to watch. It was probably awkward for them to film it, too. What makes it worse is that Justin was dating his now-wife Jessica Biel at the time.

5 Jennifer Garner & Michael Vartan: She Was Pregnant With Ben Affleck's Baby On The Set Of 'Alias'

Jennifer Garner was married to her first husband Scott Foley when she met Michael Vartan on the set of Alias in 2001. Shortly after her divorce, she dated her co-star Michael in real life.

Apparently, he was her rebound.

Their romance did not last long — the couple dated for only a few months before ending their relationship in 2004. It seems like they have better chemistry on-screen than off-screen. Like other celebrity couples on the list, Jennifer and Michael also worked together until the series finale in 2006. By the way, Jennifer was pregnant with her then-husband Ben Affleck's baby while filming the show’s fifth season. Creator J.J. Abrams decided to make her character Sydney pregnant, too, which means her ex-boyfriend, Michael's character, was the father of the baby.

4 Diane Keaton & Al Pacino: Their On-Again, Off-Again Relationship Ended Before Filming 'The Godfather III'

Diane Keaton had a string of famous lovers, but it was Al Pacino who completely stole her heart. The co-stars dated in real life after meeting on the set of The Godfather in 1972, and they had an on-again, off-again relationship for almost two decades! That’s a long time. Diane told People, “(He was) charming, hilarious, a nonstop talker. There was an aspect of him that was like a lost orphan, like this kind of crazy idiot savant. And oh, gorgeous! I was mad for him. I worked hard on that one.” After constant breakups and makeups, she gave him an ultimatum, which ended their romance for good. She said, “I went about it not in a perfect way.” They broke up before they were set to film Godfather III in 1990.

3 Hayden Panettiere & Milo Ventimiglia: The Superhero Couple Worked Together For Another Year On 'Heroes'

Heroes co-stars Hayden Panettiere and Milo Ventimiglia sparked dating rumors when they were spotted getting cozy with each other at Emmy’s party in September 2007.

She was 18, and he was 30 at the time.

They dated a little over a year before ending their real-life relationship in February 2009. An insider told Us Weekly, “It was a lifestyle conflict. They were in very different places.” Apparently, one of the other reasons for their split was because she was flirting with Jesse McCartney. Overall, it seems like Hayden and Milo did not end on good terms. They had to work together for another year, and the exes’ mutual friend told OK! Magazine, “She refuses to be on the set at the same time as him. She is making it difficult for everyone involved.”

2 Jennifer Morrison & Jesse Spencer: 'The House' Co-Stars Called Off Their Engagement But Their Characters Tied The Knot

Jennifer Morrison and Jesse Spencer met while filming the House pilot in 2004. According to People, the co-stars kept their off-screen romance a secret for four months. They dated for three years, and they even got engaged. In December 2006, Jesse proposed to Jennifer in the most romantic way — he took her to Paris and popped the question in French in front of the Eiffel Tower. Sadly, they never made it to the altar and called off their engagement in August 2007. Just because they broke up didn't mean they can abruptly leave the show. They continued to work together on set for a few more years. It was probably awkward to film their characters' wedding. Their characters also don’t get a happy ending. They get divorced in the show’s sixth season.

1 Charlize Theron & Sean Penn: The Once Happy Couple Had To Spend Time Together For Reshoots For 'The Last Face'

Charlize Theron and Sean Penn have been friends for decades before they formed a romantic relationship in December 2013. They flaunted their love on the red carpets and gushed about their romance in interviews. The couple even worked together on the film The Last Face in 2014 — Sean directed and Charlize starred. They called it quits in June 2015 after dating for a year and a half.

It was a surprise because a month prior to their breakup, they looked happy at the premiere of Mad Max: Fury Road.

It must’ve been an awkward reunion when they had to do reshoots for The Last Face in July 2015 — fresh from their breakup. The exes met again to promote the film at 2016 Cannes Film Festival where they apparently ignored each other most of the time.

References: Rolling Stones, E! News, Vanity Fair, Us Weekly, People

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