Sadie5: I can relate to what you're saying - my mother had a stroke about two months ago and then two weeks ago she had a heart attack. She's now waiting for bypass surgery. And she lives with me, fortunately, since last year, because otherwise I think the hospital would send her to a residence for elderly people, which would probably be the death of her. However, it is also very difficult to be the caregiver.
I don't understand the privacy laws in the U.S., here in Canada the doctor sat me down and explained everything in detail about why she needed the surgery, I saw the angiogram and he explained "stenosis" and "occlusion" and it was very clear that my mother has no choice but to have the surgery, she has too many blockages in her heart.
A power of attorney will be very important for you and I suggest that you have one prepared as soon as possible. Let your mother's bank have a copy also (they may demand their own form of power of attorney). Maybe in the States it's different, but here my mother's banks have copies of the power of attorney so I can access her funds when she needs something.
As well, is there some form of home care you can receive, even if it's just a few hours per week? It'll give you a break, and they usually help with bathing and meal preparation at least (once again, that's here in Canada, and I imagine you must have the same or better in the States). The hospital itself may arrange to liaison with the services available - that's what happened here.
Feel free to leave me a message if you want to vent/ask for information or whatever.