I think you just need to speak your truth.
Find a time between her being drunk and/or hungover and tell her what you think.
You can be compassionate and frame it that you are worried about her and her health, and the ongoing health of your relationship.
Ultimatums don't work unless you are going to do what you say, so I would avoid those.
How she answers you will be very telling, I think.
She may lash out.
She may be contrite.
She may promise to cut back or stop altogether.
Don't listen to the words; look at the actions.
This is a process, and nothing needsto be decided this minute, but I think you owe it to yourself and to her to be honest about how you feel about the drinking.
Peace.