Ugh, I am familiar with those conflicted feelings. You are not obligated to take care of your parents. Your father could have made different choices in his life. He could have developed a close relationship with his children. He could have found a nice senior living community (and still can). He could have taken care of his health. Just because he decided to do nothing and live in a fantasy world where his kids take care of all his problems does not make them your problems.

Did he take care of his parents? One thing I have noticed is that people who take care of their own parents seem more likely to make arrangements for their end of life care. People who expect their kids to handle everything did not do the same for their parents.