Mom is guilt-tripping poor Dad that he broke his "till death do us part" vows by putting her in a nursing and rehab center.

Perhaps if they moved together to an assisted living facility, he could live with her and have the help he needs with her care close at hand. I have relatives who have chosen options of the sort. It is something to look into especially for the progressive living. I understand such places are not in every community and are pricey, but when averaging the cost of maintaining a home and keeping a loved one in a NH it be doable. Just a thought of a way out if it gets to him, or a possible discussion for her to feel like this move isn't the end of their lives as a couple. Their home could be rented out for income and if it doesn't work, he has a place to come back to.