Could this be the reason why Jennifer Aniston and Justin Theroux haven't tied the knot yet? There's a new report that says the couple might be close to breaking up because the actress supposedly found out that her fiancé might have another girlfriend on the side.

Jennifer Aniston, Justin Theroux Wedding News 2015: Did The Couple Break Up?

According to Star Magazine on Friday, things have gone from bad to worse for the couple, who have allegedly been fighting for months now.

"Jen and Justin are in a terrible place right now," an insider reveals. "They are never together and even when they are together, they fight nonstop."

Jennifer Aniston, Justin Theroux News 2015: New Report Says The Couple Is 'Growing Apart'

To make things even worse, Theroux might be having a secret affair. The report says that the actor might be romantically linked to a crew member on his hit HBO show, The Leftovers. The pair were allegedly seen dining together in the same New York City restaurant that Theroux proposed to Aniston in back in August of 2012.

"She was supposedly a pretty blonde, and Jen and Justin had many arguments over her," says a source close to the couple. "He swears nothing happened, but she thought different, and the fact that he may have cheated has stayed in the back of her mind."

So far, neither Aniston nor Theroux have made any comments about the report.

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