If you can control how you respond (and yes, I do know just how hard it is to do this), it will help you feel like you have some power. And, truly the only power or control any of us have is over ourselves anyway.
Don't bring up divorce. I'll tell you what I said when my H told me he wanted a divorce, it was simply, "I understand. I don't want that and I won't help you." Did it help? Was it a magic moment? No. It was simply a cards on the table moment.
If I recall from your other thread, his Dad had a brain tumor and committed suicide? That's alot to deal with. Was his Dad a man that lived life on his own terms? I ask this b/c of the suicide.
There are books I can refer to you, but I would prefer to do that on the alt. If you want to look me up, I'm Grace O'Malley.