To answer the why - it's because I've been feeling guilty about not telling him. Irrationally, I think, mostly because I'd want to know if someone died on his side of the family. But I don't know if they would break silence and call me or do something else. I'm not even sure that they would, but that's something for another time.
I have decided, after listening to everyone here with their wise wisdom, to not do anything. I might say something in the Christmas card - to a PP, no, I don't do a Christmas newsletter, but I might start as a friend of mine did last year and I really liked it - but otherwise, I'm going to leave it.
Also, I did a Google search and found an online obit. It's on tributes.com from the social security death index that is open to the public. So, they could find out that she died by doing a search. I'm glad I checked that, as I feel a lot better now.
Like I said, irrational.
Oh, and to answer about this:
It's also strange about them sending birthday and Christmas cards after telling you they don't want any contact. I would nave returned the first card with a note: "You told me you want no contact, so I'm puzzled as to why you sent this. You never pothered to tell me what I've supposedly done wrong. If you are ever willing to do that, let me know."
I was so happy in the first place that I didn't question it. And I've just let it stay open all this time for no good reason, honestly. I figure that they will either tell me in their own time or die angry at me. I've washed my hands of any angry emotions of them long ago. Now I'm just curious. Plus, they might actually tell me why one of these years as a present for a birthday or Christmas. Doubtful though.