It's just a messy situation no two ways around it. Lots of judgment calls when people are too intoxicated to have good judgement.

Generally as a society we do consider people somewhat responsible for their actions when they're drunk. Like you can't say "I was too drunk to know that I shouldn't drive home." If I'm too drunk to be able to say no to someone, that's my responsibility. Other people are drinking too, and it's not their responsibility to make absolutely certain that when I'm saying "yes" to someone I might not normally go with.

Sure there can be ugly situations where someone is coercing someone, but there can also be innocent situations where someone is just flirting and things go a little further than normal because alcohol is involved. And there's everything in between.

And the shame of being considered a slut comes into it. I don't really feel all that ashamed of waking up with someone I wouldn't have normally been with if I was sober. We had sex, nothing to be ashamed of there. I had sex with someone I wouldn't have normally been with. If there's no shame in it, why would I be angry with that person?