Wow, this sounds just like me, on a bad day. Throw in the fact that mine is a long distance relationship and you've just about got it.
The thing is, I KNOW I have trust issues, and my guy has really helped me through them. Realize that you have an amazing person who is in love with you. You must be pretty damn great to deserve that, right? Just try to see all the good qualities you have; I'm sure there's a ton.
good luck
