I can't stand any longer to live my life?

Hi, I'm 15 yr old teenager girl, I've been living with my family and I've never had that real happiness in my life. I've always getting yelled at and being blamed for something I didn't mean to do. I'm a good teenager who doesn't smoke or drink. I rarely get out of the house since i'm always at home cleaning and washing dishes. I'm also doing great at school except last year, I really slacked off in everything but I got nearly all my grades back up. There was this one subject that failed on and got an F on it. My dad was furiously mad about it and started acting like a jerk. Scared of getting cursed and yelled at, i've been locking myself up in my room and barely ate for the past four days. I have a post traumatic stress disorder that's why I couldn't bear with stressful situations anymore. when i was a kid i've been through a lot. I got beat up, cursed at, and almost got killed. Which caused me to get afraid of being treated like that again. My dad was never been really nice to me, he had never taken care of me. He left me at home alone when i was younger and just get mad at me for no such reason. I couldn't take so much pain anymore. I do not know what to do.. I really want to just run away because I might have no choice than letting my dad send me back to philly... I'm scared out of my mind. I feel like I'm really alone....