Jennifer Aniston and Justin Theroux Once 'Tried to Start a Family' Together (Exclusive)

A week after their split, a source gives ET insight into what really went wrong.

We're still not over Jennifer Aniston and Justin Theroux's shocking split.

It's been just over a week since the two announced they were calling it quits after two and a half years of marriage in a joint statement, and now, a source gives ET insight into their relationship prior to their break up. 

Although Aniston, 49, and Theroux, 46, appeared to have it all together whenever they were photographed in public over the last few years, behind-the-scenes, they gradually "drifted apart."

"They tried to start a family but it never happened for them," the source explained to ET. "But that is not why they split."

According to the source, the main reason for their downfall was their love of different cities. Aniston is very much a California girl, while Theroux prefers the Big Apple.

"[Jennifer] has a very set life out here in L.A., and Justin is not that kind of person," the source said. "He was never going to go to Soho Malibu with her friends and live at the beach. I think he was the most attentive man she has probably ever had, but at the end of the day, I don't think either of their hearts were still in it."

But despite their differences, there's no love lost between Aniston and Theroux.

"They have such love for each other, but they are both stuck in their own particular lives," the source revealed. "They have very set ways, hers in L.A. and his is New York City."

"He was never going to be that guy," the source added. "Justin was present, but at the end of the day, they just couldn't make it work."

Hear more on what went wrong in the video below.

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