I think you are still too nice to her. When she is giving you all that cr@p about her suffering in her A, why don't you tell her what you are thinking instead of holding it in? She needs to hear the truth about herself!
As far as the OM goes, he gets off the hook in all of this b/c she's done just exactly what he wanted. But, she is so deep in her fog until "any" other man will do for her and her email said that!
I know you still have feelings for her, but I hope you will not give in to her and let her get her way about things. She needs to hear the facts about what kind of "mother" she is. She isn't living in the right century to think that kids automatically go with the mother. Oh, she gets me stired up! You are a nicer person than me, BJ.
It is not about what you feel should work in your M. It is about doing the work that gets the right results. Do what works!