I wanna kill my self

I let my friend commit suicide two years ago and I didn't care, but I started feeling guilty and started to cut myself and cut my hand. I don't know why. My parents says that I'm crazy and my friends doesn’t care about me even when i tell they reply with you’re a teenager and a child, or you’re just being dramatic and sensitive and I don't know what to do. I even tried to commit suicide a while ago, but I failed and I didn't tell anyone and I hate all my friends and I want to be as far from my family as possible and I don’t know what to do I’m confused and starving myself a lot I don’t know why and I’m sorry I don’t know what to do if you wanna talk to me add me on Snapchat: y3nxb