Very good post. Detachment #1 - what I've been calling the "Spiers Doctrine" -- the only way to function in combat is to assume you're already dead.
And you're right -- detachment doesn't mean you don't care about WAS. It means you don't care to let the outcome of the situation with WAS define your life. It means that Frodo Lives. No matter what. With her or without her; with him or without him.
What I know now -- what I really KNOW -- is that there's Someone Else out there for me. No matter what. She may be WAW -- new and improved. She may not be.
But the End of the Marriage, if it comes to that, is not -- is not -- IS NOT the End of Me.
I only got there by detaching. Detaching saved my life. Because it saved my sense of Me.