How do I survive school with no close friends?Any advice?

I have couple of friends and i feel as if im not close to them anymore. I'm fine with being a loner because im moving to a new school in 3 months anyway. It's not like no one likes me or anything, i'd rather be a loner than have friends that i can't trust. I feel bad because i told my friend that my other friend likes a guy and i told her not to tell anybody that i said that, but she told anyway. They act like complete bitches anyway and im sick of them. One thing im worried about is that i told my friend who i like, and i feel like she's gonna tell everybody once i become detached from them(if you know what i mean). I have other friends but most of them are in other cles and are friends with my friends. I can be shy and awkward but i'm trying to change. I know its my fault because i was being a big mouth but im not that kind of person. The only reason i told my friend's secret is because she was taking advantage of me and she treats me badly. I suffer from depression and please don't tell me to see a therapist. I cry at night just thinking that i have no real friends. What i want to know is, how do i survive school with no friends? Like, i have no one to sit with at lunchtimes now. I know this is immature but in my school, people who sits alone are clified as, "losers."