My bf got drunk and possibly cheated (need advice)

So me (22f) and my bf (25m) have been together for over a year. And I have never worried about him cheating. He had my trust and it was something I never really got too anxious about. The o lot weird feeling I had was this one friend of his from work. She had a boyfriend and we would all hangout together. She is always really nice to me and had never showed any interest in my bf in “that” way. But for whatever reason their closeness always made me a little uncomfortable. Whenever I would have a dream that my bf cheated on me it was always with her. Them being friendly always made my stomach hurt. Even though he has other female coworkers that he’s friendly with this one always gave that weird feeling. But I have insecurity’s that I’m trying to work on and my own problems that I don’t want to project I’m out relationship so I ignored it and never said anything.
Well recently I was out of town with family. He wasn’t able to go with me because he had work. On my last night he went to a party with a bunch of his coworkers. I knew this because they put me in the group chat where they plan parties. I’m known by all his coworkers and sometimes go to parties with everyone.
Well he got really drunk and I’m talking really drunk. I have never seen or heard him so drunk. The only reason I know is because he called me and left a message an you couldn’t just hear how drunk he was. In the message and talking about how much he loves me and that he wants to tell me how much he loves me. It was funny when I heard it. The next morning I knew he was gonna be hungover and not feeling good. But the next day he was supposed to pick me up from the airport. Well a long day of travel later I don’t end up getting home until about 2am. With flight delays and everything I got back late. Anyway he’s telling me that he doesn’t want to drink anymore. That he felt so sick that day and that he doesn’t remember what happened that whole night. That he blacked out. That he doesn’t even remember that voicemail.
The next morning I order him food and get him some water to help him feel better. He stops me and says “I need to tell you something” instantly my stomach hurt I knew something happened. He tells me that this friend from work (the one who always made me little uneasy) was in the hot tub with him. And that he was trying to get her to sit on his lap and kind of feeling her up I guess. He says that he doesn’t remember but that her boyfriend (who is also his friend) texted him saying that he can’t do that to her and that he needs to apologize. That he made her feel uncomfortable. I didn’t even know what to say I tell him that he disrespected me, that he’s disrespected her and her boyfriend. I told him that he needs to apologize to both of them. He said that he did say sorry and that she still feels a little uncomfortable, which as a girl I understand. I know he feels bad and feels horrible but it makes me feel gross for lack of better words. I told him that she always made me feel insecure and that all my dreams of him cheating were with her. I clarified that I have nothing against her, she’s really nice and I like her as a person but I was insecure. I honestly don’t know how to feel I don’t know how I would approach her if I see her again.
I just don’t know how to feel. He was blacked out and said he doesn’t remember but I still feel like I can’t trust him anymore.
Any thoughts?

TL;DR:
My bf got drunk and tried to have a female coworker sit on his lap in a hot tub at a pool party while I was out of town.
He told me he was black out drunk and doesn’t remember and that he feels horrible about it.
Don’t know how to feel…