I understand you must be very angry, but please calm down.
Don't divorce now. How about let the baby born first, because I don't think you can really solve this matter in a short time. Also use this time (before bb born) to solve the problems (I mean your health/emotional problem) and also prepare for the worst - so save more money or get more money from him. Seek help from counsellor (e.g. social workers, church) if needed. Prepare more for yourself first (money, place to live, job, who take care bb, etc.) even if you decide to leave.