Why cant I shake it?

For as long as I can remember I have thought of suicide, even back in elementary… I had no friends until the 4th grade. Things were okay until i shit my pants in the 5th grade therefore once again becoming an outcast. No friends in high school even though it was a fresh start I was still too awkward to make friends. Even when the thoughts are gone or I think everything is going good, it comes right back. Why cant I shake these thoughts? Im a loser and a weirdo, I have no friends and no one likes me. The only reasons I havent killed myself is because of my mom, I dont want to hurt her. Im a coward in everything I do. Im good at nothing. I finally got the courage to go for a girl and she ended up thinking I was a loser and a weirdo like everyone else does. She actually had me fooled until i found out what she really thought of me. I was a joke. Her and her friends were laughing at me. I told her things that was just for her and she told everybody…why?  I cant find a fuckin job, I dont know what im doing in college. Was hoping desperately that december 21 was the end of the world but of course it wasnt.