I'm so sorry to hear what you both are going thru. My stepmom, who was a mother to me died 2 years ago. It brought out the worse in everyone as soon as we buried her. Now I don't speak to any of them. Not my dad, sister, or stepsiblings.
Have you considered hospice? Not just for your wife's sake, but also for the family. They have couselors and alot of resources available. There is no cost to anyone. They can also help with some costs. Just a thought.
You both are in my prayers.
shelley