N, This is your time, your time to focus on you and what you need to do in order to help yourself heal and live your life to the fullest.
I know that you are worried about your xh, but you need to step back even more and allow God to work on him. The crazy wife will have to hang herself in all of this and you cannot be an active participant in this little game of pin the tail on the xh.
I truly believe she knows that you are still very much attached to your xh mentally and it's driving her nuts. If you can find a way to not allow her to get to you, all the better. Also, I'm going to suggest that when your friends/xh's friends bring the subject up of her and what they are doing, you will to nip the conversation for a while. Something is up and the drama in her arena has escalated and I do not think it's being done all by itself.
Call me an old fool, but when someone brings gossip to my door, my sensors go up because the old saying "a dog that brings a bone, will carry one". Be selective in what you say to those friends that chat about your xh and the wife.
Enjoy your weekend.
Sit quietly, the answers will reveal themselves when you least expect them to. The past is gone, the present is a gift and you need to focus on today, allow the future to reveal itself when it is ready.