Hi Single Malt,
this is a most excellent list of boundaries

The way I see the current behavior of your wife is that she is trying to adjust and is struggling to do so. It is a big change. Only time will tell whether she manages or not. There will be game playing and baiting. If she was somewhat functional without being in a relationship there is often a good chance that she stabilizes in some form. Whether that will be in or not in the relationship remains to be seen.
Don't discount validation. Just because someone knows you are doing it does not mean it does not work. Having said this - you are validating quite well here:
I have tried methods of validating her feelings and trying to tell her the truth in nonthreatening ways, but my wife has read books on BPD and can tell when I'm trying to use these methods--and it makes her mad. So, I am not going to use those methods anymore. Instead, when she begins accusing me or making statements implying deficiencies on my part that I know are not true, or blaming me in some way for her unhappiness, I'm simply saying "I'm sorry you feel that way, but I disagree. May I explain why I disagree?" --and if she says "no", which she usually does, then that is simply the end of the discussion.
We got a conflict here - care to discuss or let's agree we disagree? is spot on and not hiding anything negative.
These decisions may well hasten the end of our marriage, but I feel for me they are necessary in order for me to keep my identity. Time will tell.
I doubt the former and applaud the latter. Going back to who we were, more precisely who we should be is be an important step in our healing.