Oh gosh, so sorry that you are going through this. God knows a newborn is enough stress! Please think long and hard about how to handle this, maybe even seeking some outside help from a therapist. The situation is not good the way it is and I'm afraid you will need to be very strong to get it back on track, IF that is even possible.
I might tell your husband that the only way the marriage can continue is if you go to counseling.
You don't say if this is his only child??? I would think the thought of NOT being in this child's life full time would be enough leverage to force him to make changes. He needs to though, and you must insist on it.
Good luck....think about who will be there for you in your old age?? Your son, your new child (if you expose him/her to this chaos) or the husband. To me, the answer is clear. Big hug!!!