H4H, read your "this is how it might go" script -- YOU'RE PROJECTING. You've tried it YOUR way; why not try something different?
CALL THE QUESTION. At worst, you get her to say to you "I refuse to even TRY the best way to ensure I end it with him." At least you'll have CLARITY, and from where I sit (and where I've been), "clarity" it something we ALL need more of.
There's a world of difference between someone who refuses to end it, and someone who says they "can't." It's time to find out if your wife really is in the latter camp, or if she's just full of it.