I dont know what to do?

Okay..I know this might be long but I need advice..okay I can really explain thw whole deal but something happened to me that caused the friends I trusted most to not like me, even though it wasn't exzactly my fault. I counted on them, so I was really shocked and felt abandoned when I found out they didn't like me anymore. So after that I kinda went downhill on the making friends front. I have become antisocial, and only find myself saying hi to those I feel more comfortable around(which are the social outcasts or "weirdos" in school) I have become a major loner myself, and find myself attactching to other loners because I feel it is my only safe route. I'm deathly afraid of being in public because I know I don't make very good impression with people, and I always end up screwing something up. When I try to be friendly and be myself, everyone takes it the wrong way for some reason. I try to be nice and humbled but people react to me like I ofeended them. I have been told that I look too serious and oissed all the time. I'm am a very sensitive person which most people sont realize and I admit I do have a lot of issues at home and everything. I come to school thinking "everythings cool todays a new day" but it just ends up in the same old routine of feeling defeated...I have a lot of insicurities about myself. But when I try to be confident, it like people can see right through me and know I'm faking and just make fun of me. It feels as if I'm always being kicked when I'm down. And I'm down a lot. My life is so depressing that i have to have a reason to smile. I want to be like everyone else and not worry so much about things, but its so hard not to. I don't get how people can walk around so carefree..and i all I want is to be normal and not have to worry that anything that comes out of my mouth will be weird or that I look funny or if I'm coming off the wrong way. I want to cry all the time and do almost every day....yes that's a lot but ill take any advice right now