Abusive relationship aftermath

Hey guys, my little boy is 11months old. I just want to make this quick as I really need some help and advice. I am a young mother (please don’t judge me). My ex partner and the father to my child, was manipulative and abusive, he got me on drugs, he gaslit me, he lied he cheated (I think) and used coercive control, physical, verbal, mental and sexual abuse against me for over a year and a half. I lived with him because of reasons such as I thought he would hurt himself if I left. Around 2 months after I had my son, I decided to leave. I couldn’t take it anymore I would wake up crying everyday and realised my son couldnt grow up around that. Around 8 months now since I’ve left and I have ptsd, depression, anxiety and everyday just feels worse and worse, I’m exhausted and am not happy but I pull through. My worry is that I miss my ex partner. I have thought about him more and more over this Christmas and I miss him and I miss what we had when it was good. He loved me so much when it was good, I know it wasn’t healthy love but there was certain little things he did that showed he genuinely did care. I couldn’t go back to him now though, the police are involved and so is court. He would hate me for taking his son away from him for 8 mo yes of his life he won’t get back, but I dont want him around my son I know what he’s like really. But I have never loved someone like that before. I did everything for him and let him say things and get away with things id never let anyone else do and I don’t know why. I miss him so much every single day and I want him back but that isn’t okay because he broke me as a person I’m not the same as I used to be and I don’t know how to go back to that, I was always so happy and friendly and social and now I don’t have the energy to answer messages or speak to people (I wasn’t allowed too when I was with my partner) and now I have nobody. I’m so alone. Please can someone offer advice on how to get over this as I cannot let my child back into that situation no matter how much I struggle or how weak I get I need to get over him please can someone help. I’m begging. I’m so tired of feeling this way.