Soon after Justin Theroux and Jennifer Aniston announced their split, fans were determined to figure out what went wrong. Now, one month later, Life & Style has exclusively learned that he “put her through hell.” And it wasn’t just rough for Jen at the end of their relationship, either — apparently, they were doomed from the get-go. The source explained that Jen said, “It was never a real marriage to start with.”

It was a classic case of opposites attracting — she liked game nights in with her celebrity pals whereas he would rather hit the town — and the source revealed that it was soon after they started initially dating that things took a turn for the worse. “It didn’t take long for their different personalities and relationship expectations to clash. They’d fight for weeks at a time!”

jennifer aniston and justin theorux

And when the fighting persisted, Jen would seek out her friends for comfort. The insider claimed, “There’d be many times when Jen would drive to Courteney Cox’s house in tears because Justin was ‘being a nightmare.’ Courteney has always been there for her BFF and advised her on how to deal with Justin’s behavior, but nothing Jen did seemed to work.”

The Friends alum tried to salvage her relationship in 2016 when she flew to Berlin to surprise Justin on the set of his Netflix movie, Mute. But after they talked about recommitting to their marriage and even discussed having a baby, it only led to more arguments. The source said, “They waffled so many times.”

jennifer aniston justin theroux getty

But despite their disagreements over starting a family and their different lifestyles, Jen simply couldn’t trust Justin. “Justin is a classic ladies’ man and flirt, and it always drove Jen up the wall,” the source shared. “One of the worst moments for Jen was when she started seeing Justin flirt with her friends. Women are very drawn to Justin. All her celeb friends were charmed by him at one point or another.”

One person, in particular, was Selena Gomez who has been close friends with Jen for a while. The source said the “Bad Liar” singer was “nervous and blushing” during a Golden Globes afterparty a couple of years ago when Justin wouldn’t stop complimenting her. “[He told] her she looked great. Justin has an intense way of looking at you that makes you feel special and a little weak in the knees. It was awkward for everyone, except Justin, and really hurt Jen.”

And that wasn’t the first time he really had made her feel like garbage. “There would often be times when Justin promised he’d come to LA and then canceled at the last minute,” the source explained. “His excuses made Jen question what he was up to. In her eyes, she was putting in all the effort and getting nothing back. Jen would tell pals that she felt more alone being married to Justin than she did being single.”

Life & Style reported that Jen had reached her breaking point in the marriage and days later, the couple confirmed their split. The statement from Jen’s publicist, Stephen Huvane, read, “Normally we would do this privately, but given that the gossip industry cannot resist an opportunity to speculate and invent, we wanted to convey the truth directly. Whatever else is printed about us that is not directly from us, is someone else’s fictional narrative. Above all, we are determined to maintain the deep respect and love that we have for one another.”