Need advise

I was in a relationship with a guy and he was everything to me but I have a daughter and I had issues with my dad so I wanted to try to work things out with her dad so the guy I was with supported it well my daughters dad was mentally and physically abusive when I finally left I stayed single for a little bit but realizes that the guy for before going back was literally everything I could ever ask for...so I went back to him. My issue where I need advise is I struggle with fear trust and I’m going threw a custody battle with my daughters dad so I’m haveing a lot of issues letting my walls down and trusting my boyfriend what do others do to help work past the fear and anger that is involved with the trauma and how do you keep it from effecting the person you love