Actually another option would to be to really take charge of the divorce proceedings. I don't want it but I also don't want to be married to someone who has an A and thinks of me so badly.
I think a few have done that in the past, and then regretted it. You do want to take charge of your own life. You do want to be a strong leader and have more alpha (especially at home). You are still getting information for yourself in ways to improve. However, I don't think you want a D, and beating her to file first does not show the kind of "take charge" you need right now. Unless you know without any doubt that you are through with her and the M, I wouldn't do it yet.
Have you checked with a lawyer to see about your rights, etc.?
Didn't you say she was moving out as soon as she found a place of her own?
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!