Officially a single mom

I just got up the courage to break up with my toxic, emotionally abusive/manipulative boyfriend, officially making me a single mom. I'm not worried about being a single mom, I've basically been one so far. But for some reason I'm still sad....even though I know I should feel liberated. The new fear now is if he decides to file for custody and the ensuing court battle. I want him to have a relationship with our child if he wants to, but I don't want him to have 50/50...I don't think he's truly capable of that with where he is I'm his life right now.