According to E! Online's Marc Malkin, the couple, who began dating in February, are no longer an item.
"Ryan and Audrina are definitely not together right now," a source who was with Audrina over the weekend in Las Vegas claimed. "It's still a touchy subject for her."
The reality starlet was in Sin City on Saturday hosting a party at the MGM Grand's Wet Republic – but Ryan was not in attendance. He was reportedly across town at Leona Lewis' birthday bash at Vegas' Pure nightclub. Audrina and Ryan reportedly spent the night apart.
"Audrina's not talking about it," the source added, "But, people were talking about it over the weekend."
The starlet's pool party wasn't the only recent event that she showed up to without Ryan.
"Audrina came to Perez's birthday with a girlfriend," another source said. "When she was asked, 'Where's Ryan?' she made a mortified face and changed the subject right away. She gave off a weird vibe and seemed very awkward."
The couple's romance was filmed for the upcoming season of "The Hills," but there is no word if their reported split will be featured.
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