Re: CN "I know that when his W was well, had she known that this would happen, she would have given her blessing to this R". CN that is the way I am thinking now if I had Altziemers or something else like it, and did not respond to family members.
Good for you if you encourage him in his new relationship. If he and the OW/lady friend see his W once a week, I say they have big hearts. I say the guy and maybe the woman went through a lot of lonely times and have earned some happiness.
Who knows what the two of them do when thet are together. Maybe the act like room mates (BTDT, it sucks) or maybe they act like lovers.