OK. So we had a huge fight last night about a bunch of things related to the affair.
It ended in probably the most honest and productive conversation we've had in years. The cliffnotes are:
She wishes more than anything to be able to turn her feelings off for the OM. If someone could tell her how, she would.
She has grown over the last 5 years and is a totally different person while I have stagnated (true).
She is not in love with me and says she didn't really feel like she was cheating because in her mind she left the relationship a year ago and is totally over it. To the point where if I dated someone tomorrow it would have zero effect on her and she would probably be happy for me.
We started dating when she was 21 and she was married at 24. She now questions if the feeling she had for me were ever true love and maybe she just jumped into marriage too early and we are really not compatible (I don't agree).
So I told her I thought the best thing was to sell the house and get two separate places. I said we have kids and we are married and we've never once tried to fix our relationship so it is worth at least one try - she finally agreed to seeing an MFT but not until December.
She has also agreed to see my therapist who agrees with DB and Michelle Weiner-Davis' approach for several "separation sessions" and maybe for individual.
So for now I am going to truly focus on me and start working through my own issues. If she comes back and we can rekindle something then great - if not then at least we can have closure instead of being endless 'roomates'.
Thanks everyone for helping me work through this extremely painful and life changing process.