I agree, file for divorce & if you can, get legal aid so they will be able to help you get what you deserve for support, in particular for your unborn child.
I married a narcissistic /psychopath who had previous wives who supposedly abused & cheated on him. He was a liar & has a very long history of abuse, lying & cheating, which I had no idea until later.
He didn't pay me a penny of the debt & he's not garnishable.
You would be WISE to file the divorce papers & seek legal aid.
These types do the same thing over & over, they don't ever learn. You are fortunate it sounds like that he is gone & moved far away from you. I know it sounds cruel but I am speaking from experience, very similar situation.
Do everything now in regards to him, through legal system. Will pray for you.