Chris Brown Breakup 2014: Karrueche Dumps Singer Over Rihanna Photos

Chris Brown is single once again after his girlfriend, Karrueche Tran, discovered he "liked" a photo of himself and Rihanna.

After years of ups and downs in their relationship, most of which have been over Rihanna, Brown and Tran have parted ways.

"Karrueche exploded when Chris recently 'liked' 2 fan photos on Instagram of Rihanna and him together," TMZ reported on Aug. 1. "But Rihanna was only a small part of Karrueche's problems with Chris. We're told she was unhappy for a long time ... as sources put it, because 'Chris acts immature, like a child.' She thinks he's ruining his life by spending more time partying than making music."

Brown and Tran's relationship began in 2011, shortly after his messy split from Rihanna. And although the pair appeared to be quite stable throughout that year, 2012 was a different story. Despite Brown having attacked Rihanna in 2009, the pair was seen together several times and reports claimed they were rekindling their romance. In October of that year, Brown confirmed he had ended his relationship with Tran, noting he didn't want her to be hurt by his friendship with Rihanna.

Brown eventually got back together with Rihanna in Jan. 2013, but by May 2013, they had split.

In addition to Brown's reported "liking" of the photos of him and Rihanna, TMZ claimed the singer took one of Tran's close girl friends to St. Tropez with him -- and was sure he and the mystery girl were photographed together.

Tran has reportedly changed her number to ensure Brown is unable to contact her.