In the depth of your own illness you try to outwit hers.
Hide the car keys. For tonight and tonight only that's one tiny victory: she won't be dying before sunrise from a DUI wreck on one or another back road. Where the downside is that she'll take out the frustration by doing her damnedest to wreck the house, or the cat, or you.
Maybe you can snatch the bottle from her hand, pour it down the sink before it goes down her throat. Unlikely outcome. Before blacking out she's as fast as you, and, the likelihood anyway is that she has more bottles hidden.
Search the house while she's passed out. There's a pint in the toilet tank. So that you're actually offended for her by the crude stereotype. It's pointless anyway. For all you know she has cases more buried in the yard. She's perfectly capable of planning ahead.
Ultimately your behavior is just as sick as hers. You're trying to shoulder responsibility for her sobriety. That can't work. She does it, or it doesn't happen.
You can understand the instinct. And forgive yourself for it. You're trying to keep yourself safe. From the violence and the chaos. You're trying to keep the house safe. And yes you're trying to keep her safe, too.
You can't keep anyone safe. You have to make the decision: am I going to live like this, or am I going to stop it?
Granted your own safety is at risk it's not a real option.