Straight acquaintance kissed me and I feel awful about it

TL;DR: I have a boyfriend who wouldn't be okay with this. The guy is for sure straight, he'll be upset when he remembers and he'll convince himself and everyone that I started it. My friends will likely judge me as it's trashy, sloppy and out of character. I feel like absolute garbage and it's nothing to begin with. What do I do?

I had a party (ended up at a gay bar) and this guy was there as a friend of a friend. I interact with him a lot, but I'm not friends with him and I don't care for him. My bf wasn't there (currently long distance).

He got extremely wasted and was grinding on me and was grabbing my ass jokingly. At this point, it's not weird as that was more or less average compared to how everyone was dancing. I thought it was all in good fun because it's not sexual as he's straight, wasted drunk and we're not each other's type at all. I think he also knew I'm gay but I'm not sure. Then at the end of the night, he comes to say bye and he goes in for a very tight hug which was fine and I hug back. It felt very nice, but it definitely had an oddly romantic tone the way we were moving our hands and placing our heads on each other's shoulder. We do that for a bit and I'm telling him to stay because he's the life of the party and then I start picking him up and swinging him in the hug. When I put him down he goes in for a kiss on my lips, continues on my cheek and nuzzling me. I wasn't really kissing back, but I didn't push him away and I don't know why. A gay friend who was more sober and knows no one wants to do this comes over and says night's over and pulls me away.

It was really fucking awkward as I thought/know he likes a girl friend (there yesterday) and I have ~1% interest in him, even if I were single. It felt sloppy and trashy and I would have preferred to stop at a hug as that felt like we were bonding and good.

It made me feel awful on top of the drunk feeling so I went home. I still feel like shit today because 1) as the gay guy and the guy in a relationship, I feel like I should have stopped it because it's bad for me, not him. It's not like I was fighting him off of me the entire night, I liked the dancing/no consequence touching leading up back and forth 2) my friend will be upset and not say anything 3) he'll be upset and not say anything if/when he remembers 4) my bf will likely overreact if/when he finds out even though it meant nothing to me 5) it wasn't even that good for it to ruin the night and several relationships.

I feel uncomfortable and upset now and I don't want to see the guy. I'm thinking of avoiding places he'll be and I can't even think of a best case scenario where everyone doesn't hate me. I'm embarrassed it went that far. I feel like I fucked up and I don't know how to proceed.