I'm sensitive and I hurt in my relationship :(?

I've always been sensitive, but since my bf and I got back together my emotions have been all over the place. A part of me wants to dump him, and a part of me needs someone to talk to (since I don't have any TRUSTED friends). I can be super happy one day, and he'll say one little tiny thing and I'll end up crying over it all night! Like today, he was getting people from the musical (he was in it too) to sign the brochure. My name was in it (I was backstage and stuff) and jokingly I asked to sign it. He replied with a "no... Its special and I only want the actors to sign it.". I totally understand that, but for some reason I can't help crying. I think it might be from the rejection. There was another time when he commented "okay kitty ;3" on some girls picture after a conversation and, yeah, I cried again. I'm just so...so insecure still. I don't know what to do, or how to feel, and its driving me crazy! Please help :(. I'm such a cry baby, I know. In my defense, he did break my heart once.