I agree with Rosey. You need to define and stick to some reasonable boundaries.

I have 2 grown children. One is very responsible, the other a bum. I will gladly help out the responsible one, but not the bum. It seems your parents are playing the parts of irresponsible children. I suspect they will take every advantage of you until you are drained as dry as they are.

You might look into any senior services available in your community. A disinterested 3rd party might be able to help your parents face reality, solve some problems, and not get snarled into a self destructive mess like you face.

Good luck, and thank you for helping me see my parents in a better light.