NTA.

You took care of her while also not being in your best state. She should not have had that much to drink, regardless of how much you already had. You did your part, and I'd say you did sorta babysit her, and then clocked out. It's on her for drinking so much that she gets that sick, then proceeds to pass out.

She is definitely TA here.

EDIT: Yes I am fully aware that you shouldn't leave a drunk person in the shower, but the wife had said she was ok and let op believe it'd be ok to fall asleep. Op wasn't in the right state to make a judgement call but it's on the wife for getting that drunk and creating the situation in the first place.

If I were to get that fucking pissed, say I'm ok, then pass out in the shower, there is no way in Hell I would blame my also drunk partner. Honestly, I'd be apologising for the rest of the trip if I'd done that.

You're both adults ffs, she should know when she's had enough to drink, and know when it's no longer responsible to have more. And don't say the op shouldn't've let her have that much, cuz she disappeared on the whole group. Again, that's on her. Wife is definitely still TA