First question......when or how did this discussion come about? Who made the contact?

A preacher who tells church members personal business is not good! If you can't trust him to keep things confidential, I suggest you not share with him. This is very touchy for your W, and I can see why. As far as him taking your side.........that may just be her VP.
Has she known him a longer than you have? Have you had a close relationship with him, or shared any other experiences with him?

If he should take it upon himself to talk to your WAW, I doubt she will be very receptive. And, I don't think you should ask him to talk to her, b/c of how she feels toward him.

Attending church is a personal decision that the individual has to make. However, I don't suggest you try to show her a 180 by going to the same place Sunday. I can see several reasons how it would not be in your favor, but mainly b/c your thoughts would probably be on her & her family, instead of worship.

In other words, don't go to church to make brownie points with her, but neither go to another church trying to avoid her. Don't miss going somewhere, b/c you need the spiritual encouragement.

So, pray about it and seek God's guidance.

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!