Stay detached, mysterious, interesting. Busiest guy in the room. Look good/smell good. Courteous, even engaging, but not NEEDY, not "MELTY MAN" and not PURSUING.
Make sense?
Let her come to you. And when she does, your answer is "Hmmm, I'll have to think about that. I'm not sure how I feel about that (getting back together to work on the marriage) anymore." or "I'm afraid it's not that easy anymore."
A wayward wife losing her attraction for OM1 is only 1/3 of the battle, Arc. If you don't RE-attract her, by working on your GALing and your self-improvements, she will more likely turn to an OM2 than she will to return to the marriage.