I feel like im dead inside, please help me?

It's been a year since my family pes away and when I was first adopted, you would think I would be coping well by now. But really Im not, coz the people I live with make it much harder. They don't care about anything I tell them, they don't care! I have gone to self-harm (cutting my wrist) And attempts and thoughts at suicide. I try to force my self to just move on and try and tell myself that I can get throught this...But it's not working. I alwasy think about how I wished I had a family again and stuff, I mean... It's tearing me apart. I live in an abusive home as of now and I feel like I can't do anything! I've lost my voice, I've lost my smile. Today my teacher pulled me to the side and said "Momo, you never talk and smile much anymore." And I said "I forgot how to" I really am forgetting how to talk to people because where I live, everything I say is wrong and I get tourtred for it. So I just keep shut, and at times keeping shut is wrong too. Im COMPLETLY jelous of other kids, I want there mom and dad sometimes. Sometimes I can see a lady at the store and just because she look nice I wish she was my mom. And I hate cutting myself But I feel like I need to be punished becoz Im not letting myself be happy..if that makes any sense? I really don't know...im 13. But I don't even act like Im 13, Im not even a kid any more it seems. My head say "Im just waiting for something to kill me, so i don't have to do it myself" What's wrong with me, Im getting really tired now. I feel really really despret having to look on here for answers to something so personal, But i have already been to a theripst and everything And it did me no good. I feeling like Im diying, And i feel like I have no reason to be here....And I know I am NOT the only one in the whole world that feels this way, But im hear still amoung the rest and I need as much help as they do.