I need help 😔

So me and my boyfriend have been together for over a year and we have a baby due in December but we have been going through so much.. he drinks and he knows i dont like it because how he treats me when he drinks. Today he packed all his stuff and left all because I didn't want him to drink tonight like he has been every night for the past 2 weeks.. i love him so much and its so hard to just let go.. 2 days ago he hit me and thats never been a issue since the beginning of our relationship when we were both really drunk and got into it.. i just love him so much ... i dont want to let go but i know its the right thing because im pregnant and i dont need this stress in my life.. or to be hit.. i just wish it was harder to let go

UPDATE

So i just logged in his snapchat to be nosey and he has my "bestfriend" SAVED UNDER HIS FUCKING MOMS MAME . and she sent him a snapchat a hour ago. I had a feeling about this fucking bitch. Ive been sitting here wasting my fucking tears for a piece lf shit ass guy im so fucking pissed