I was in an abusive relationship and now Im the abuser

My story starts way in the beginning but I will try to keep this short. I was abused as a child/young teenager. Both parents abandoned me at different points in my life. I got pregnant young and thought the wrong person was the father. I loved the person who I thought was the father of my child. But it destroyed him when it was realized he wasn't. We stated together sort of. Had a child with him shortly after my first. I moved away and he moved with us some time later. The relationship was physically and emotionally abusive plus he constantly cheated. But I felt I deserved it since I had hurt him so badly. I waited for him to change. He left us. Didn't see him for several years. We got back in touch and he came to live with us to be a family. I never had moved on. Never had another boyfriend. I just waited for him to love me again like when we were younger. Even after 10 years, and him being s horrible father and a horrible man to me, i wanted to be a family. I was then 25 and got pregnant again right away. The physical and emotional abuse continued through my pregnancy. So did the cheating and humiliation. He had also developed a massive drinking problem as well as a drug addiction. I hated my life. I hated him. I hated waking up. I hated myself for making my kids go through this. But i was stuck in a way that i had no way to take care of the kids without him. We ended up moving back home and we separated. He was again never around for the kids etc... He decided he was going to change again. And I decided to try again. Things were good and we have gotten engaged. He is good to me and the kids. He is encouraging and loyal and my best friend. It's been a year of him trying and me testing him. He is selfless and loving and a wonderful father. He is completly drug free and he doesn't binge drink anymore. I am happy... Or at least I know I should be. I know I love him. And I know I'm supposed to forgive. After all, he forgave me for how badly I ruined him when I thought he was my child's father. He knows im not that stupid girl i once was. His family forgave me too. I love them and they live me. I'm supposed to be in a happily ever after scenario right. But deep down I feel an anger. And it was brought to my attention that I hit him a lot. And then I realized I do. In a playful way at first. Like a playful swat. Now it's progressed into punching him "playfully" or pushing him. But when I think about it I hit him several times a day. He has told me I make him feel stupid. And after thinking about it, I do. I use sarcasm to make fun of him or to make his feelings seem worthless. I can see I'm the abuser now. How do I stop this? How do I stop this swelling anger I feel deep down? How do I forgive and forget? I don't want to be the person I am. I want to be the kind and supportive person I used to be. I feel like that part of me has been smothered and died. I have a real problem with developing relationships with others. I literally have no friends. But I prefer it that way. Even with my family, I don't feel the bond I should. I am a closed off person, willing to turn my back on anyone as long as it prevents me from being hurt. I love this man. I want help. I know I need counseling but that's just not in the budget. I can get a book though or maybe something like that. Any help or suggestions would be so appreciated.