Pregnant and alone !?

I been with these person for the past 2 years I have two boys with a previous marriage know I'm pregnant 6 weeks and idk what to do these person I'm with just drinks too much has gave us a though 2 years I really am excited to be a mommy again but idk if I'm making the right decision on giving my baby a daddy that's not even gonna be their ! We are separated but I just don't want him in our lives but by me having the baby he wants to be around in these relationship alcohol had a greater advantage than us as a family please no judging