(((Kay)))
Here's what I'd do...

... and then a little bit o this ...

... and finish with a little bit o this ...
Yer friend seems to be doing a lotta this ...
Tell her aloha ...

... then go outside and continue merrily with your ...
It kinda reminds me of my best friend who is a recovering alcoholic. Way back when I took her and her 2 daughters in many times. Watched her vomit blood in the morning, walk to the freezer, and commence to suckin on a new bottle of vodka.
Then it started wearing on me really bad. She kept digging herself deeply until she was impossible to be around and I asked her to go home. We didn't speak for almost a year. Only then did we speak because she ended up in a hospital for treatment and I took her daughters for 2 months.
The lady needs to quit taking advantage of you and go home and if she doesn't have one, needs to find one and go there. Your health and sanity are too important. She's taking huge advantage of you.
I see why you're worried to ask her to leave but...as we've talked about before in some instances...if she's going to do herself in, she's going to do it.
And right now I'm berry

at her!
I have some great ***** kickin boots and be there in a moment's notice if ya need some help.