Adds another source, "They've remained close."
The duo recently spent a night together late last month at New York City's Bowery Hotel. "Jen was there on the arm of John and they were all very lovey," says an onlooker. "She was in casual clothing as was he, and she seemed very comfortable around his crowd of friends."
Aniston, 40, and Mayer, 31, first called it quits in August 2008, only to reunite months later for a short time – and then split once again in March after a very public appearance together at the Oscars.
At the time of their most recent split, a source told PEOPLE, "Jen got her feelings very hurt and she is done with John for good. They have no contact for now."
Reps could not be reached for comment.
Reporting by PERNILLA CEDENHEIM, ALEXIS CHIU AND ANNEMARIE CRUZ
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