I'm really worred about my brother he had a different dad and his dad was abusive and my brother made some bad misstakes he won't talk to any of the family but he talks to his dad I seen him at sub way once he looked at me and my mom and he left my mom tells me its not my falt but I can't help but think it is and that he doesn't love me any more he cuts himself and barly leaves his house and doesn't work I'm afraid he'll try and kill himself but ever time some one tries to talk to him its like he gos farther away

Just pray for him. Do you believe in God? He answers prayer, I know.
He is probably lonely and has low self esteem due to the abuse he endured from his dad. Emotional scars can last forever. Just keep trying to befriend him and show him you really care and are not there to judge him.
Depression can be fatal if not treated. Is he taking medication? Consider talking to mom and see how you both help him get to a doctor. Sounds tough. Good luck. I'm glad you care enough to ask.