Sounds like he was in the throes of pronounced Alzheimer’s and possibly doddering around the house for a number of days after she passed from Hantavirus. So she was laying dead in the home and he was probably confused and scared and had no idea what to do before passing himself from his own heart disease and Alzheimer’s conditions. Probably exacerbated by her not being there to help him stay hydrated, fed, properly medicated. What a terribly sad end for both of them.