girlfriend in New York City for her Diamonds tour, Brown celebrated his 24th birthday with a big bash in Hollywood. He was accompanied by several friends -- including, notably, ex-girlfriend Karrueche Tran, whom he dated for a year before getting back together with Rihanna.
A source tells Us Weekly that Tran arrived at Emerson Theatre with the "Don't Wake Me Up" singer's entourage and was by his side at the table when the night first started. However, she disappeared from the group a short time later.
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"She didn't look very happy," the insider says of the model. "He didn't appear to be paying much attention to her and was partying around a lot of girls."
Brown and Tran have a complicated history together, to say the least. A few months into their relationship, Us Weekly broke the news that the R&B star had been secretly hooking up with ex-girlfriend Rihanna. Then, in October 2012, Brown broke up with the aspiring model amid more reports of his infidelity, telling Us he loved Tran "very much" but didn't want to "see her hurt over [his] friendship with his ex.
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"When you share history with somebody, then you tend to fall in love with somebody else, it's kinda difficult," he said in a video posted just hours after he confirmed the split to Us. "Is there such thing as loving two people? I don't know if that's possible, but for me, I feel like that."
Tran, for her part, spoke about the saga earlier this year. "It was very hard," she told Rolling Out magazine in January. "I try my best to just ignore the negativity, which is hard for me because it's a lot to deal with. But I try to keep a positive mind and stay strong and not put energy into it."
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"At the end of the day, he will always be a friend," she said to Vibe magazine that same month. "We'll always care about each other."
Rihanna, meanwhile, has been busy traveling the world and hasn't had much time to devote to her romance with Brown. As one source puts it, "The tour is her life right now."
This article originally appeared on Usmagazine.com: Chris Brown Parties With Ex-Girlfriend Karrueche Tran While Rihanna Is on Tour
