David,  your note first of all makes me think of a friend who’s father had Alzheimer’s.  The mother said she couldn’t handle it and was a very anxious person.  Family didn’t take it seriously she died before her husband by starving herself to death.  Please take her needs seriously, even though your father is ill.  Its hard to address different processes without knowing more about the stroke and what his needs, deficits are.  The other point is that if she doesn’t want to care for him , he will not get good care.