Rita came with him and Larry from Pittsburgh, remember. And he had (apparently) years to learn all her shortcomings before February 3rd, so he knew what he was getting into. Part of his progression is that he was forced to get to know her as a person, rather than become a sex partner.
“He was an old man. Sometimes people just die.”
In my mind what he ends up doing is finding him early in the day, getting him a good meal, and then checking him into the hospital and telling them to charge him for all his medical expenses. He knows he won’t be able to save him, but this way he can give him a peaceful, warm last day.
Could be.
But I agree he has to die in order for Phil, nearly-omniscient and borderline-omnipotent as he’s become within the city limits, to recognize and accept that there will always be some things beyond his control.