It's over for Audrina Patridge and Ryan Cabrera after about four months of dating.
A source tells UsMagazine.com the two split "a little over a week" ago.
"Things started to go awry the night of her birthday and she ended things after that -- pretty much the next day," explains another insider. The Hills star spent her 25th birthday, May 9, with Cabrera, 27, in Las Vegas at Liquid Pool at Aria, then later that night at Las Palmas Latin Supper Club.
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The biggest issue?
"Ryan’s a constant partier and that became an issue," says a source.
"Audrina was crying at Wango Tango," adds the source, referring to the weekend L.A. concert in which Cabrera performed. "MTV made her film and she didn't want to."
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The former couple first dated several years ago, and then rekindled their romance last January. They were spotted holding hands while vacationing in Mexico in February.
Patridge's last on-screen romance was with Hills costar "Justin Bobby" Brescia, and ended last year.