I feel like my life isn't going anywhere?

I feel like no one wants me here, I feel unseen. My life has hit a bit of a snag and I dont think its going anywhere? I constantly feel depressed not only with that but how i look. I have just managed to stop cutting myself after having done it for a while now. But lately it looks really appealing to pick up that knife. I have no-one to talk to and I just want to scream! I feel like im trapped in a box and im running out of breath. What should I do? Bear in mind I dont want to tell my mum and dad.