Ive always been a screwup

Im 17 years old. 18 on November 22. I just lost my dad on March 22, a little over 4 months ago from liver and kidney disease. I watched him suffer, deteriorate. My hero started needing me for help to do the simplest of tasks.. I had to help him up after the many times he had fallen. But now hes dead. He was in the hospital for a few months before he died so somethimes it doesnt seem like he is gone. But I never wanted to go see him in the hospital. You see his illness made him say some mean things. He could never understand how a young kid could be depressed. He couldnt understand why I never wanted to talk. He thought I hated him. But now I miss him more than anything. Growing up I was daddys little girl, as a teenager I was daddys little nightmare. I just want to be with my daddy, I miss him sooo much. Back in Feb. of last year I met a guy. Someone who knew what it was like to have someone you loved be sick and who knew what it was like to be depressed. I was a cutter from nov. 2011 till he made me stop after he found the scars sometime after June. I loved him so much I would have done anything for him. He took my virginity in june and then told me he loved me. We didnt have a very good relationship. I took a lot of risks being with him and since he was older he took a lot of risks being with me. But he controlled me. He still does and he knows it. He broke up with me in may of this year. And for a few months it was like we were still together just without a title, Sex and all. And then he started being distant. And thats when I knew he was fucking another girl, but hey we werent dating right. Hes been fucking with my head ever since but he says he just wants me as a friend nothing more, he doesnt want a relationship and he doesnt want me. I dont want any other guys. The thought of another guy having sex with me actually makes me sick. So Ive begged for him and begged for him but he wont take me back. And I know I need to let him go but I cant I dont want to move on. At first he was my best friend and I could rely on him annd I told him all my secrets and he knew exactly what to say. But now things are completely different and Im the failure who ruined it all. I just want to die. I just want to be with my daddy. The one and only guy who will never stop loving me. I have attempted suicide, but im a failure, remember? Im so lost so confused and so fucked in the head. And I just want my daddy. But if there is a heaven and hell I want to go to heaven with my daddy… But if not I will be dead and it wont mattter. I just want to die. My life sucks. I have nothing to live for. My mom is dating again, and my dad just died. Shes dating my neighbor. She has no more time for me. Im just a wasted space. And now im just want to end the pain and suffering. End it all. But how… What is the best way?