As for the conversations, it is hard for me to say as this is something I am still working on myself. Everything I've heard has been not to discuss R with WAS unless they initiate. However, as my FT says, it doesn't hurt to plant seeds. A lengthy conversation when the WAS is not going to truly listen anyway does no good. You can't rationalize with an addict when they aren't looking to get clean! BUT, if you can say something to plant a seed without being emotional about it, maintaining your dignity, and it's from a position of confidence and self-respect, I think it is good to do so.
I'll give you an example that my FT thought I did a good job with:
A few weeks ago when H had initiated a R conversation, I mainly just listened and did not say much. I just looked at him matter of factly while he stated that he was not sure he would ever feel the same way about me. (I'm not saying it was easy - but I kept my poker face.) I replied to him that it was not surprising he would feel this way given his background and how easily and quickly his family members detach and run. I said it like a therapist would - not in an accusatory manner, not any commentary about it being unfortunate or sad - not a thing about how I felt... Then I turned to walk away and he replied, "that's true, actually."
The thing is, you can't allow yourself to get into conversations where you will lose your position of strength. YOU have to be the one with the answers and not get emotional.
