By Jodi Guglielmi
December 04, 2015 at 06:08 PM EST
Jason LaVeris/FilmMagic
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This article originally appeared on PEOPLE.COM.

When Brad Pitt and Angelina Jolie Pitt began filming By the Sea, they knew they were going to discover new things about their relationship. 

One big surprise? Jolie Pitt, who directed the film, admits it was especially eye-opening to see how they both react in the aftermath of a blowout. 

“Brad has never seen what I’m like when he’s left me after one of our fights,” she told French Elle for its December issue. “Sometimes I’m strong. But as soon as he leaves the room, I melt into tears.” 

“With this film, he sees it,” she added. “And I see into his private moments.” 

Jolie Pitt, 40, said that seeing how the other copes after a fight helped them understand one another better in their real-life relationship. 

“I filmed it and I discovered his expressions,” she explained. “So I better understand his frustrations over certain aspects in me.” 

Set in 1970s France, By the Sea tells the story of a struggling marriage between Vanessa (Jolie Pitt), a former dancer, and her writer husband, Roland (Pitt). 

While the couple in the film is not based on their real relationship, Jolie Pitt said it was still hard to separate their real feelings from the ones they were supposed to portray on screen. 

“The most difficult scenes were the most drawn-out fights: normally if Brad sees me cry, it ends by his taking care of me. But here, in the the film he had to stay angry, and I couldn’t take it personally,” she said. “It was so strange and interesting.” 

By the Sea is in theaters now.

2015 movie
  • Movie
  • R
  • 122 minutes
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