Who even does this? 😔

Now I know arguing, or often having disagreements with your significant other isn’t healthy. But is it healthy for your significant other to pack up and just leave because of only that specific reason? I’m 3 months pregnant and he says he just wants peace but my emotions are obviously everywhere and he says I’m not ever giving him “peace”. Mind you he says he doesn’t wanna try couple therapy because I won’t understand even though it’s ME who offered for us to go and get things right.. Right now he’s choosing to live at his friends house.. His friend cooks him a lunch every morning before he goes to work and even does his own laundry 😔 he lives there rent free & only gives them his food card so I guess that’s helping.. I feel so replaced, sad, & lonely.. Well to add more hurt he came over last night & I don’t know when we woke up I just felt off so I asked him “if he’s been talking or texting anyone” and he legit says yes. & That he is the one who gave the women his number. (Were still married btw..) Mind you he left me cause of our “petty arguments” and says I’m the one who needs to make him wanna come back and be my husband. I’m so lost and hurt right now, being 3 months pregnant and all this just happening at once while I’m supposedly “married” sucks, I’m in disbelief and shock. I didn’t even go off or anything hearing that I just asked him if the women he is texting knows I’m pregnant and he replies no as well.. says he wasn’t even trying to take her on a date or anything.. I paid his phone bill Friday and barely got texts from him, I feel highly stupid and sad but I can’t fall into depression I’m afraid it might take a bad toll on me 😔😔 ladies I just need advice, criticism, idc this honestly sucks.. what should I do? I’m willing to co parent and all of that but I’m so tired of being sad and thinking things will just fall back into place..