Paris Hilton just found her new BFF on her MTV show, but could she already be looking for a fresh replacement?

While My New BFF winner Brittany Flickinger accompanied Paris to Sundance, it sounds like she was seen as dead weight by the party-loving heiress.

Instead of hanging with Brittany, Paris befriended former Danity Kane member and current Playboy cover girl Aubrey O'Day.

Paris reportedly left her supposed BFF at the Hollywood Life House. Later that night, when Brittany caught up with Paris and Aubrey at the Axe party, the twosome left her behind in the bathroom.

"She ran out and was like 'Wait for me! Don't leave me in the bathroom," according to an eyewitness.

So what's the problem with Brittany?

"She just has no personality," says a source. "She seems like a waste of space."

While her rep wasn't available for comment, Paris apparently moves quickly...casting calls just went out for the second season of My New BFF.

But if Brittany's getting the boot, she doesn't seem to know. She just blogged on her MySpace about spending Sundance with "her favorite girl." Stay tuned!