Opposites don’t always interact. Sometimes, they repel. As Jennifer Lopez and Ben Affleck take some time apart to determine the fate of their union, a source exclusively reveals to In Touch the moment the couple knew their marriage was falling apart. “The making of her documentary [The Greatest Love Story Never Told] was a real eye-opener for them,” says the source.

In one scene, Ben, 51, shares how shocked he was to learn that while working on her album This Is Me… Now, J. Lo, 54, had given the love letters he’d written her to songwriters. “Things that are private I had always felt are sacred and special in part because they’re private,” the actor tells the cameras. “So, this was something of an adjustment for me.”

J. Lo admitted as much herself, too. “I don’t think he’s very comfortable with me doing all of this,” she confesses in the doc. “But he loves me, he knows I’m an artist, and he’s gonna support me in every way he can because he knows he can’t stop me.”

Ben didn’t, but things did change between him and J. Lo after that. “They both sat back and looked at how different they really are,” dishes the source. “While Jennifer loves being the center of attention, Ben would rather live his life away from the spotlight. At the end of the day, they both just want different things out of life.”

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