Why am I treated like a mutt in society?

Why am I so disregarded everywhere I go. I'm never invited to parties, people don't think I have a life, and i'm never picked for anything (atleast that's how I feel). Is society treating me like a misfit because nobody ever called me a misfit? Guys and especially girls just make me want to cut my throat because of their mediocre involvement in my life. To state further, I don't get the fullness out of life like I should. And also I get this feeling that I am being left out on a precious part of life. Even worse, I think the guys are less guilty and I just could not forgive the world as a result. How could anyone keep me out of sync from this kind of happiness?