Once a cheater...

So I recently moved into my new apartment in the last week.. tonight my boyfriend and I got into an argument over some girl, a neighbor who knocked on our door at 11pm to invite him out to smoke some weed. And I have nothing against him smoking, if I wasn’t 9 months pregnant I’d be smoking myself. Anyways I’m laying in my 3 year olds bed trying to get him to fall asleep, it’s taking longer than usual tonight for some reason and that’s when I hear her knock. And all I hear is him saying “oh awesome” and close the door. He runs into our room and throws on a shirt (and im pretty sure some deodorant) and pops his head in saying he’s going out to his car. And didn’t tell me why until I questioned him. So I make it very obvious I didn’t like it, and told him to do whatever the fuck he wants... which he knew meant if you go do this be ready for hell. And the motherfucker goes out there to smoke. Then texts me saying “calm down it’s two guys and Maria”... like I give a fuck or believe what he says. And I know it doesn’t sound like much but before I got pregnant he’d sleep around so much, and I didnt know about 90% of it until after I was pregnant and far enough along where I had to make a decision to get passed it or leave. And raise another child on my own. Clearly I stuck around. And the women I’ve seen him talk to... he really would’ve cheated on me with ANYONE. really I mean anyone.. he slept with his friends mother (which he denies) and plenty of women, there isn’t one type he’d deny. Older, bigger, he really would’ve stuck it in ANYTHING. I was really appalled when I saw the people he cheated or tried cheating on me with.. so clearly our trust issues stem from the fact that he had no self control and was talking to 50+ women while we were together over a year, before I got pregnant. Even slept with his ex and said he wanted children with her.. which broke me when I saw that pregnant with his child. I wanna be able to trust him but I honestly know that I can’t, I won’t. And now being in an apartment building which is primarily college girls is so worrying for me. And I know I’m overthinking because I’m 9 months pregnant and feeling shitty about myself but I can’t even look at him right now. so he comes back in from smoking with the girl and I’m ignoring him, sitting in my nearly empty living room and hes acting like everything’s fine. It’s not fine.. he doesn’t get it. I’m not trying to hold the past against him but c’mon after cheating so many times what do you expect. Not to mention he called me a little girl, pathetic, told me to grow up.. I dont even wanna sleep in our new bed together, we just spent 4 grand on a bed and I would rather curl up in my sons bed and just be alone.. why are men so oblivious. Somebody tell me if I’m overreacting please 😩 I can’t stand the thought of him cheating and I just signed a year lease in his paradise, so many girls around here and I know he’s an attractive guy.. I don’t even wanna think about it right now. Not even a week into living here and he’s already got girls knocking on the door at 11pm to smoke and not to mention they haven’t even said one word to me when I’ve seen them outside or in the hallways, not even a smile. I don’t trust anybody