I don't know sweep--I know how triggering the whole situation is to you, but it sounds like you communicated to this guy in various ways that it was consensual. If you were incapacitated from drinking or had said no/pushed him away at some point then, yes, it would be assault.

But to be fair to the guys, we need to let them know when it isn't ok. If you follow through with a kiss without pushing back or saying no--they are left with the idea it is ok.

Maybe you feel guilty/shame for what happened? By framing it as assault, you put all of the responsibility on the other person.

I hope you can work through it! Confusing past abuse with current events won't help you.