Personally I wouldn't tell her. I would work on the poly stuff first and keep the other woman at bay. Let the six months ride out and see where you are at when its over. Quite often these things dwindle and then there was no reason to cause drama. I would just let it go for now... at the very least. I am glad you are excited and NREing on poly, but take it for what it is and see where it goes with your wife. The other woman was the catalyst, but not necessarily the second woman of your dreams... why complicate it. In six months if you still feel for her, then maybe its time... by then you will have learned some stuff and be more settled in what this poly shit means to you.
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