Hi, welcome to the board. It may be a little slow through the holidays, but keep posting.
With reading only one post, I am hesitate to anyone to go ahead and file for a D. If it serves you better in the financial aspect, I think you need legal advice about your timely filing for the D.
As for your W, don't believe the b.s. she told you about the OM. She gave the most typical lie that wayward wives give. She actually left you b/c of this OM, with whom she was having some type of an affair. That's why he just suddenly and conveniently appears on the scene.
Read the page from Cadet, carefully. Be sure to read the links. It will help get you started on the DB path.
It is not about what you feel should work in your M. It is about doing the work that gets the right results. Do what works!