Im 13 weeks pregnant and my now ex bf started doing ecstacy and drugs and partying and clubbing everyday ?

Idk what to do bc now he has picked the girl he partys with over me and the baby. And I guess they really like each other. Idk what to do. He texts me sometimes and gets mad if I talk to other guys and I don't talk to them like that. I wish he would relize he is making a mistake. What should I do about this? Someone plzz help