drunkenness makes your decision making worse, but it doesn't spur something like that outta nowhere. Her judgement was impaired so she said the quiet part out loud. Still means that she's previously entertained that thought (i.e. 'yet') and still she acted on on it. you don't hang around somebody and their boyfriend for TWO YEARS and hit him with the "why haven't we fucked". Giving somebody the benefit of the doubt SHOULD be your default for small-stakes issues, not this. It's a fundamental disrespect (and gross of her!!) and if you chose to move forward staying friends with her you are asking for more bs like that. And we all know being drunk doesn't obsolve you from the consequences of your actions.