I don't expect them to disown a member of their family. But I expect they'll break ties with my W like they did her mother years ago for doing the same thing. If they don't, then so be it. I would out the warning out there and mive on with my life. If my W is busy trying to take the place of his W, then her coming back is the last thing I would be worried about.
Once the ink dries, I am going completely dark. W would have to do some serious begging and repenting at that point. And by the time she gets to that point, I highly doubt I will even want a wife.
