I hit him

I don’t know what to do. Things with my fiancé hasn’t always been the greatest and it’s been on and off again for the past 4 years. I thought since I came back this last time that things would change because we have a 7 month old baby girl. I never wanted to keep his daughter away from her father so I came back. Well we got into a gnarly argument that turned into a huge fight. He kept egging me on telling me to go ahead and hit him. He was calling me names. Like cunt. Fat shit. Dumb fuck etc. he got in my face and I started hitting him. I’m not this person that is angry and an abuser. I snapped and I don’t know what to do. I know that I am taking my daughter away from this toxic environment. But would you turn yourself in for abusing someone? That’s what I mean by I don’t know what to do. Over the years of being with him I’ve put up with his manipulation and abusive behavior. Mentally physically and emotionally. But when I came back. I thought things were changing for the better. Until tonight.