The best advice I can give here is that you should not make any decisions - or even communicate with your W if possible - when you are emotional. Use this place for that.
Try to look at the bright side, which is that at least your wife seems to be very confused. I am willing to bet that when she has a bad day with the OM, she comes back to you. That's how the fog tends to work.
I think you need to resolve now to start making her feel the consequences of her choices - i.e. do not enable her. Do not help her financially. Do not treat her as a W (telling her where you're going, etc).
Do NOT take any responsiblity for the divorce - meaning don't push here to take action, and don't take action yourself. Have a plan or several plans, but don't share them. She wants the D. She needs to take ownership - and she is pushing your buttons in part because she wants you to absolve her of that dilemma.
Don't do it. Don't make this easy.
Work on you. Distract yourself with doing things until doing those things becomes natural.
