Coming to terms

When I was younger my dad, a heroin addict and ex USMC, Would lash out and hurt me in every way he could at the time (in front of family it was just verbal, alone it would get physical) he would "brainwash" me as they said in court and distorted my self image and my image of family and love. It was for four years roughly. 7-11, when finally on my 12 birthday after harming myself they took me out of his house. Im 17 now, and haven't seen my dad since i was 13. We did supervised visitations until I turned 13 when he stopped showing up because he didn't want to waste the money. Causing me to go into a depression and overdose on the medicine they prescribed me for the first attempt. My mom and stepdad hated that I was acting like this and made me feel worse for not dying. They were ashamed that they had a "sick child". I finally stopped talking about this. They refused to pay for therapy and the topic was never brought up again. I never healed. I never relearned the ways to love myself. To love others. Ive become a very cold person and it takes a lot for me to even care about someone. Any tips on how to become less of a cold hearted person and to move on from the pain that still hurts even after so many years?