Aniston, 49, is a California girl at heart, the source said, while Theroux, 46, has always preferred New York City. The source confirmed to Radar that neither were ready to give up their desired coasts.
"Justin spent most of his time in New York City without Jen," the source said. "Jen tried the whole living in New York City thing with Justin. New York City just wasn't ever going to be home for Jen."
Aniston and Theroux made the bombshell announcement that they're separating after two years of marriage on Thursday, Feb. 15, just one day after Valentine's Day.
However, the split was a long-time coming. Radar exclusively revealed the couple had a brutal fight back in December 2014. The fight ended in an angry Theroux storming out of the couple's Los Angeles home.
The source told Radar that Aniston's idea of compromising with Theroux was allowing him to live in New York on his own without her.
"Encouraging Justing to spend as much time as he wanted in New York City is what doomed the marriage," said the source. "Jen thought by doing so, spending time without her would make Justin miss her more"
The source continued that Jen believed her absence would make the big apple "less desirable" for her husband if she wasn't there.
Ultimately, the Friends actress' plan backfired.
Justin ended up "happier living on his own," the source said.
The split also boils down to the fact that the couple have different personalities.
"Jen is very laid back, likes to be with her friends all of the time, while Justin is reclusive and introverted," the source said.
In a joint statement released Wednesday, the exes vowed to continue their "cherished friendship." However, Aniston has already listed the Bel-Air mansion where she married Theroux up on the market, Radar reported.
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