Send him the dirty note, if you think he'll like it. Don't do it because you think that you need to prove anything, do it because you love him and think sexy about him.
As far as the monster - he cares. I don't know why, but he does. Can't you both change job locations? It would really help your marriage. I'd also be more agressive towards monster - actually, I'd probably have physically smacked her or something, I couldn't hold it together like you have. But don't back down, let her know that you have the upper hand by the way you carry yourself. Park next to her. Put something your H has given you in the window. Show some cleavage. Brush past her on your way somewhere, treat her like the trash she is, but in a classy way.
