Thank you for posting this.
WH is my best friend, we're totally compatible, we had a great marriage before the A, and he's a model of R, and a terrific dad.
Yet, I have "daydreamed" about him dying. Of course I do not really wish for this at all. I think it comes of feeling like I don't have any good options. I can't divorce him because of kids, finances, family, friends, and the annoying fact that I love him. So, they only way for me to get out of living intimately with my betrayer is if he died.
I know intellectually that it would be 1000 time worse than this if he died. But my heart is in so much pain that emotionally, it seems like it would be a relief on some level.
I don't think these thoughts are a sign of anything other than the human heart dealing with betrayal.
If it helps, my WH sometimes thinks of death (not suicide because he knows that would be incredibly selfish and he's not actually suicidal). As time goes by and the reality of what he did sinks in, he is in more and more pain. I'm not ready to be compassionate, but he truly would rather dead sometimes than feel the loss of his integrity and face the pain he caused me.