My girlfriend and I are having trust issues.. please help?

My girlfriend wants to live on campus for a school that she lives like 20 minutes away from. She says it's important to her "college experience" but I think that's just a bunch of crap. I've been cheated on by every single one of my girlfriends but this one has never done anything that would lead to me losing trust in her...the problem is I just don't trust any girl after dating those other ones. I gave her an ultimatum of either living on campus and losing me or living with her parents or me and staying in this relationship. I need advice and quickly because I'm in a bad situation. Please help. Thank you.