They're 19 and 23 so certainly old enough for the conversation in that way I think. They both already know that my W was the one who left of her own free will. Just the way it shaked out.
After sleeping on it I'm thinking about, "Mom and I disagree about how best to continue our relationship and deal with the problems that exist between she and I, and while I don't necessarily support her decision to divorce, I do support her as an individual and intent to accept and respect her decision."
I'm trying to be both accurate, honest, and positive towards her in some way. Does that come across as too "I'm the good guy and she's not"?