Though Hills stars Lauren Conrad and Audrina Patridge recently patched up their fractured friendship under the warm, nurturing eye of multiple video cameras, a brand-new rumor has both girls on the outs yet again. Says E!:

Audrina, we’re told, is fuming because she found out that her on-and-off lover, Justin [Bobby], and former BFF, L.C., hooked up behind her back...Supposedly, A-doll has been running around town trying to find out any info about the incident that Mister Bobby himself has supposedly confessed to. Lauren denies it, natch.

In fact, Conrad denied it today to In Touch, claiming, "These accusations are so crazy it's difficult for me to take them seriously. While my usual taste in guys isn't always perfect, I do prefer they shower regularly." Crisis averted? Not so much — now Patridge has taken to her own, product placement-choked blog to basically accuse Conrad of mascara-running crocodile tears:

I woke up this morning and it seems like just about every gossip magazine or blog has a story about Lauren hooking up with Justin. I'm not sure what to believe. Though Justin and I have not been exclusive for quite some time, these rumors are very confusing and hurtful. I can't comment on whether they are true or false.

While Patridge might simply be teasing an upcoming staged storyline on The Hills, it's also possible that Conrad went off-book, bedding Audrina's ex in a shocking, Stephanie Pratt-worthy about-face. Where's Whitney's shocked face when you need it? [Photo Credit: AP]