Sorry about your setback. It is true that every once in a while something will come up that sets you back on your heels a bit. Hang in there, they get fewer and fewer as time goes by (though I'm not sure they ever go away completely).
As for the OM, it seems to me the greatest punishment he'll get is actually "winning" your STBXW. She sure seems the booby prize to me. Let him find the truth in the old saying, "Be careful what you wish for, you might just get it".
Now...get the D done! It's time to put this chapter of your life to rest. Quick Ds may cause people heartache, but after a D has dragged on, getting it wrapped up is a tremendous relief.
