"I have given up hope in trying to get through to him in any way - his ego can't let him hear a thing I have to say."
No, you haven't, or you wouldn't be trotting out the old stuff for the CO-PARENTING session. This is not about your old-R. This is not about his significant other who WILL be in your children's life for the forseeable future.
If you want him to see a difference, then simply act differently. Don't let him take advantage of you. Stand up for yourself if he starts dumping on you IN THE PRESENT. Trotting out the old stuff is merely more of the same, it will show him the same old stuff, it will be counterproductive.
Respond when it is appropriate at the time -- if he says with the C that you hate him, then clarify it at that point. But quit going back to past stuff.
Right now, your email to the kid's C is all about your agenda about old stuff with X. Drop it. Work on it on your own time with your own C. You will never get what you think you need from X to feel better, you have to find that all by yourself.
Remember, this session is not about yesterday. It is not MC.
Let tomorrow be about the future and about having a better co-parenting R for the kids.
