Credit: Donald Bowers/WireImage for DSQUARED2; Jon Kopaloff/FilmMagic

John Mayer recently posted a series of silly Twitter posts debunking rumors he hooked up with Kristin Cavallari. She thought the Internet gossip was funny as well.

"I literally met John one time for five minutes," she told Wednesday at an Alize-sponsored launch party in NYC for fashion blog "I am single, I'll tell you that. I'm 22. Why have a boyfriend? I'm having fun."

One rumor that is true: She and Hills costar Audrina Patridge don't get along.

"We literally just don't see each other," she told Us. "I don't have a problem with her. If she has a problem with me, that's a whole other story."

Cavallari — who made her reality show debut at age 16 on MTV's Laguna Beach — said it's fun to be back in front of the cameras.

"It's been such a great experience for me and brought me so many opportunities," she told Us of being on reality shows. "I definitely have a personal life. I only film three days a week, so I don't put my real friends on camera because it will ruin friendships."

As for her new stint on The Hills (the fifth season starts Sept. 29), she told Us, "It's fun to play the bitch."