Jennifer Aniston is back in NYC! 

The 49-year-old actress was spotted in New York City for the first time since announcing her split from Justin Theroux in February. Aniston was all smiles, looking casual in jeans, a gray T-shirt and a matching coat as she left Nello restaurant on Tuesday -- just three days after she and Theroux both attended Jimmy Kimmel's son's birthday party in Los Angeles. 

A source tells ET that Aniston is "back in her old New York routine, staying in midtown [at the Four Seasons], instead of downtown, where she had started staying instead when she was with Justin.”

Theroux, meanwhile, is in Los Angeles. The 46-year-old actor was photographed rocking his signature black leather look as he arrived at the Chateau Marmont hotel after a night out in Hollywood with friends on Monday. 

A source told ET after the pair's breakup in February that one of the major factors in their split was Theroux's resistance to the Hollywood lifestyle. 

"He much prefers being [in New York] and that's been a major issue for them for a long time," the source said, adding that the actor's roots are deep in the Big Apple, and that his friends and social group, which Theroux holds close to his heart, are all based in the city.

“Justin has a very diverse friend group, and he likes that they're not all 'in the industry,'" the source continued. "He's friends with people in the restaurant world, writers, comedians, artists, tattoo artists. It's an eclectic group and he doesn't have that type of network in L.A."

And while Aniston grew up in New York and started her career there, ET's source said that she "just never really could get settled in. She wasn't happy [in New York]." 

See more in the video below. 

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