Very sorry to hear, Complex. It must be awful for you. Almost all of us have been there, so we understand. I hope that we prepared somewhat to this "revelation". It should have been almost a given that it was happening.
It may be hard to understand, but your plan doesn't change much. You give her space, GAL, etc. the whole DB. The fact is that you CAN'T stop the A by opposing it. It has to come from her. She already told you she wanted to separate, so she can't go any further. If anything, it will puzzle her if you look like you don't mind. The more you oppose, the more value you give to the A. You feed what you emphasize.
Good luck. We're alongside you.
M39 D6 D3 (at S) S 2014-09 D 2016-09
"You can't start a fire sitting around, crying over a broken heart" - Bruce Springsteen.