BD,
My prayers go out to you and your family.
I was in a similar situation with my mother a decade ago, unfortunately I was still drinking. This probably has occurred to you, but you are there for your parents in a way that you simply couldn't while you were still drinking. It doesn't change the situation from your perspective, but I guarantee that it does from theirs, particularly your mother. That much is in your control, and you are doing what is possible. The rest, you have to trust that it will turn out as it is intended.
During this difficult time for you and your family, do not forget to take care of yourselves. Rest and eat as well as possible - illnesses like this take their toll on everyone involved.
Edd.