Some men and women can do this, but I was one who couldn't. I could not want my H and want the OM at the same time. There would never have been OM if I had desired my H like I should have. I have read LBW's talk how their H's can be in an A with OW and come home and go to bed with them as if nothing was going on. That blows me away! Maybe your W is one that can do that. She wants you both or else her ego wants to "see" if she can have both men desiring her. It may be an ego game with her. She may be cake eating.
I would not "tell her" that I was dropping the rope......I would just do it! It needs to be done "before" she makes any trips to see the OM. I believe since she is doing all this flirting and trying to keep your attention that there is "something" that drives her to do it, so dropping the rope sounds like the idea LRT. I believe it is the ONLY thing that might possibly turn her back for meeting with the OM. If you have been pulling back from her, then that is why she is trying for your attention. So, just think of the possiblities if you totally dropped the rope!
Sandi
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!