There is nothing I can say to ease your pain just that I totally understand everything that you are writing because I travelled the same road with my Mom. And I have no regrets because I was there for her and helped her through to the best of my ability.
Some things are not in our control. So we control what we can. And that should be to be a comfort to your Dad and an advocate for him if need be with respect to his care and his wishes.
Praying to God to give you the strength to cope. Also praying for your dad. Miracles do happen. I just experienced one.
