I feel lonely at times?

well I wouldn't say I'm one of the prettiest girls but some people tell me I am daily or so they tell me..I live in California. But anyways, I feel lonely at times. I'm a Senior, and I always get invited to parties, kickbacks, clubs, etc. and sometimes I don't go because I rather be at home watching a movie, or being with my family. Anyways, I always get invited to dates, and for some reason I push guys away, no matter how sweet they are. (perhaps because in my last relationship I was heart broken) so I no longer do I find meaning in "relationships" although inside I wish I could give them another try, and all my friends get mad because they're the "hottest" guy. I have an outgoing personality and I'm very friendly so then why do I push people away? sometimes I even push my friends away..