Should i divorce my drug addicted husband of only 7 months?

My husband and i met approx 4 years ago. He has a ten yr history of drug abuse and jail time. We had so many ups and down because of his drug abuse. I felt i knew "the real him" but i was wrong. i believed the real him was this amazing amazing caring loving generous man who could do no wrong in my eyes and who loved me unconditionally. But his addiction overtook him. And this last time he depleated our unborn childs account (i was 5 months pregnant at the time with our first) and when i confronted him he threw things. shattered them. and tackled me to the floor sitting on me and screaming in my face. i knew he had been using the past couple of weeks and i tried to get him to talk to me, to go to meetings to call his counseler but hed lie and lie and lie and i felt so worthless and so beat down from all the previous times i guess i threw my hands up. It wasnt until he tackled me to the floor did i decide enough was enough. (i misscarried our first child and was a high risk pregnancy this time) he left for work and i packed up and flew to tx to my family. he went thru a binge and is now telling me he wants me and his child in his life. hell do anything. and if i cared at all i wouldnt take away his chance at being there when shes born. if i cared at all i would leave my family and go back to him to work through this because after all we are married. for better or for worse, (my family does not like him, they said if i go back i am cut out of their lives forever because they can not watch me and their grandchild go down because of a drug addict) i understand we are married. and i love him with all my heart. and during our 4 years iv provided him with everything he needed to get clean and stay clean. i tried doing what all the books and internet blogs say to do. I dont know why i even married him knowing deep down hed continue to relapse. I know he is a very very good manipulater and is good at telling me what i want to hear, he knows what to say to bring me back to him. part of me wants to believe he has changed for good this time. but the better part of me says hell never change. and if he cared at all for me and his child he would have utilized all his resources and tried harder to stay clean, he would chose to tell the truth instead of chosing to tell a lie. he wouldnt have spent all the baby money. he wouldnt have tackled me to the floor. I know an addict addiction is an overwhelming thing for them and they lose themselves in it and the best thing for an addict is love and support.. but when is enough enough.. when do i stop jepardizing my life and the life of my unborn for him? I believe he wants to be the man knows he is sober.. but i dont think hes ready to give up his addiction, or he is until he gets stressed out or i give in to what he wants. i dont believe in divorce, but i dont believe in having my child grow up in that environment more...