AIO? my boyfriend went home with other girls from the bar

So basically, me and my boyfriend have been fighting a lot recently the past few months but we’ve been together for 3 years so I’ve been assuming it’s just a phase and we’ll get passed it.

The other night, he asked me if I minded if he went out to the bar with his guy friend but he’d be back by midnight, but told me if I wanted him to stay and watch a movie like we planned he would do that. I told him it was fine and to go have fun. Well, I’m upstairs in bed and hear him and a few other people come in the back door downstairs at 3AM. Way past midnight. I hear him, and two other girls. They’re all obviously drunk. The girls are laughing and saying stuff like “where’s your girlfriend? She’s not going to beat me up right? Can we leave a note for her? I just want her to know we were here, I promise we’ll make sure she knows there was no cheating involved” and kept asking him to go drink and their place instead.

They were also talking shit about me, saying how the house was dirty and they couldn’t believe that I left our house so dirty instead of cleaning for him, and how I didn’t clean despite living in HIS house and they would do such a better job than him. (FYI, it’s OUR house, I pay more bills than he does and work twice as much as he does).

I started crying, he told them he couldn’t go with them, and they left. He must have thought I was asleep because he was surprised when I was sitting up in bed when he entered the bedroom. All I said was “get out”, he started screaming at me at the top of his lungs and then slammed the door and left. I cried myself to sleep. When I woke up I checked his location, he was still at the house those girls lived at. I messaged him multiple times, no response. He came hour around 2pm. We argued more, he said he didn’t sleep with them he just went home with them and passed out on their couch.

Honestly, I don’t believe him at all. But also, I have BPD and am told that I’m overdramatic. I am upset, but I’m worried I’m paranoid. But I feel like there’s no other explanation other than him having sex with at least one of them. I know I’m not overreacting about being hurt, I deserve to feel hurt, but AIO by believing that he had sex with one of them?