My gut feeling is to confront her about her affair and find out if she has ended it. If she hasn't, I want to kick her out of the house and out of my life
Are you sure that's what you want to do? Be sure that it's not just you wanting to do "something", like you have every since this started.
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!
