i cut my dad off now i want to cut my mom off.

hey guys, so i recently cut my dad off completely because i’m so tired of getting pushed around by a narcissist. My dad has never been a good person he’s an alcoholic/addict. He’s always been one, looking at pictures of me and him as a baby he was so unbelievably high it breaks my heart. My mom was 17 and my dad was 27 when they met. My mom smoked the green stuff when they first met then she got into doing very bad stuff i don’t know if i can say on here. When my older brother was born they were both on stuff, my mom would bring random dudes in the house when my dad was at work and my brother saw. He already cut both my parents off. Now for some context on what they did to me - when i was 4 and one of my brothers was 7 my half brother (same dad not same mom) touched us. Now at that point my mom was gone she left when i was not even two years old. My dad never believed us that he did anything. my half brother recently got in a lot of trouble because he beat his baby momma. My dad got mad at me because i didn’t pick my half brothers side on this. Why would i pick his side he touched me. He’s only 27 and does blues if you know you know. all i can say is alcohol and drugs are so bad, they turn people into zombies at this point. I definitely feel guilty cutting them off but at the same time all they did was hurt me. I was a chubby kid and my dad was so embarrassed of the way i looked he literally locked up the food and when my clothes would get too big he would reward me. I struggle with eating pretty bad now. He would constantly say he was gunna go take his life ( i actually have videos of him saying it) i quit living with my dad when i was 11 and quit living with my mom when i was 14, I went back and forth a lot with my mom and dad as i got into middle school. They both didn’t want me so they just sent me back when they got sick of me. i’ve been living with my grandma a few years now. And too add onto this my mom would get so drunk when i was in 8th grade and she would lock me out of the house for days. I would sleep at the park or at my friends houses. i lost a lot of friends during that time. I look back at everything that has happened in the past and i’m just thankful i didn’t do anything i would regret. Feel free to ask me anything or tell a similar story. I do need some advice tho i feel pretty bad about doing this but it hurts me more to keep them in my life where they constantly bring me down and hurt me mentally and physically.