If your W is not involved in an EA/PA, and based on the information you have given, I think she is wanting to be romanced. There is a difference in being romantic and pursuing. Yes, romance is a "form" of pursuing, but it is not to be needy, clingy, weak, no self-confidence.....those type of negative pursuits. A man can be romantic and be very desirable, but if he shows these negative traits that I've mentioned....it will turn a woman off. When you said your W apparently wanted you to pursue her when she left you, I think it was in a romantic way.....and not in any non-appealing sense.
Some men do not seem to know how to be romantic and the poor W starves for it. If that is your case, then you need to do some reading up on the subject. When she said she wanted you to "date" her and see how things go......that was your clue.
I know I am saying the opposite of the advice you received from one of the board members on the other thread, but that is what I picked up on that your W is desiring. If you suspect an A, then of course you do not need to romance her, but I did not read enough details about the stitch, to know if you did or not.
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!