Kristin Cavallari, known for her unvarnished opinions on the MTV reality show, says she's a better person than she's portrayed on the show – and that the real Kristin is the one who's been doing charity work recently.
"If you asked my real friends, they would say I'm definitely not a bitch," Cavallari, 23, told PEOPLE on Saturday while hosting a party at Liquid Pool Lounge in Las Vegas. "I definitely stand up for myself, and I'm not not a pushover."
Cavallari's plans for life after The Hills, whose final season premieres Tuesday, include helping those less fortunate via the One Kid One World charity. "I was just in El Salvador, and we rebuilt this whole school," she says. "It takes so little time, but it impacts these people for the rest of their lives."
One thing she's not interested in pursuing – a feud with Hills costar Spencer Pratt, who recently wrote on Twitter that Cavallari and Audrina Patridge tend to dress like it's Halloween.
"I heard one little comment he made, but if that's it, I'm fine with it," Cavallari says. "He's attacking everybody else. There's so much going on, and I only know bits and pieces. I'm trying to stay out of it because it's so stupid."