If she works a job, I would say to tell her if she is going to stay with you she has to put every extra penny into building a fund to be able to move out on her own, even if it is just renting a room somewhere. Make it clear the ultimate goal is for her to move out. You cannot carry on this way.
This. And yes. You need to take care of YOU. It's not uncommon for alcoholics to outlive their spouses -- we tend to wear (and worry) ourselves sick when caring for an alcoholic.
I can see several options: Go back to work, put your granddaughter in preschool, and give your sister a move-out date. Tell her her drinking is affecting your family negatively and it's time she grew up and took care of herself.
But first -- take care of YOU. (((hugs)))