I've definitely felt similar to you about scaring/burdening friends before, and have more than a touch of that paranoia myself at the moment, *but*, as a friend of mine reminded me the other day, you can always lean on a true friend: that's what friends are for. Talk to your friends and explain as much as you can -- or direct them to information on your anxiety and depression: if by any chance they do run away scared, harsh to say, but you'd be better off without them.
I'm one of the survivors of rape here (wow -- I actually feel quite empowered just saying that). I was probably about the same age as you were, and I have never told my parents. In fact, it was a long time before I told anyone, and an even longer time before I truly understood, rather than just said, that it was rape. The guy who raped me was also someone I thought I could trust -- what I had considered a good friend.
Well, I won't pretend it didn't take a lot of time, and a lot of help to put the rape behind me (including from one brilliant boyfriend, who, though in the end was not "the one" for me, is someone who is truly a friend and who I'd trust with my life). I also know that there are still some residual behaviours that jump up at peculiar moments that definitely lead back to that event. But, while I'd *never* go so far as to say it was a blessing in disguise (far, far from it), I am a stronger person now than I was then, and my experiences (good and bad) have made me what I am and on the whole I'm pretty ok with that!
You mentioned also stress at school. -- I can only begin to imagine! -- School was in no way the "best years of my life". I was a bit of a misfit and was bullied by what I can only describe as a "pack" of girls. Well, I wondered if it would always be like that, but I got to uni and found out that there really were others like me, and I made some great friends. The "pack" look pretty pathetic to me now. That said, I remember the feeling of being in the thick of it... ugh. I don't know what's going on for you, but I hope you can find ways of getting away from it. Well, you can come here for starters!!!
Take care Butterfly, and stay in touch.