Am I being irrational to expect him to stop drinking/drugs when I'm pregnant

Myself and my husband have been together for 7 years now. After years of trying I'm finally pregnant with out first child (currently 24 weeks) we met in a pub and have spent a lot of our relationship drinking and taking recreational drugs. Since being pregnant of course i have completely stopped everything for the health of me and the baby. My husband however sits here and drinks 2/3/4 bottles of wine on his own. Same as the other posts I've seen he is loving, caring not abusive and really does during the sober times have a good head on his shoulders but the drinking is constant. I have talked to him and asked him to slow down or only go on a big night in social settings and he agrees but yet the very next day will have another 2/3 bottles. He has now promised that afrer xmas he will stop for a few months af least but i dont think its enough! I spoke to him today about how I'm feeling not just with the drinking but with the whole pregnancy that I'm out of my element I have never had sober fun and im feeling a bit lost and disconnected we had a good chat and he did ask me did I want to do an activity like bowling etc but at this stage he had drank 2 bottles of wine and had drugs on the way so no I didnt want to go anywhere with him. This has kicked off a massive fight because I feel like I'm giving up everything like my body, my life and my fun but he gives up nothing and please don't get me wrong I 100% want to do that for my baby but I also feel so alone. He's asked me to go to the pub and it's like he really doesn't understand. I don't want to sit there with him chatting shit and love bombing me while I'm sober it's annoying and an utter turn off. I really am so lost as of what to do and I don't want to put him in the bad books with my family and friends but I'm alone! Is this what my life is going to be like? Just me a dog a crying baby and a drunk husband? Is there any changing this situation?