Completely understand that .... the thing to remember is her crisis started before BD. In my case it was about 2 years .... like you I just figured there are some issues and its just part of the day to day grind of being married .. the ups and downs .. little did I know her MLC brain was taking over and formulating an exit strategy .... this is why we call it Bomb Drop, its out of nowhere and shocks the LBS into panic mode. Its why we all find sites like these.
Well ... the bomb was dropped by your W, You can not undo this .. it has happened, and she will continue her assault until she has felt she has attained her objective. You now have a support group, a way to get better despite all this. Continue the basics ... Detach, GAL, keep your PMA up and start doing some activities you enjoy .. stick to it .. rinse repeat.
I have told this a few times, for me this stuff was tough, I wanted to die, sleepless nights, the BD diet in full effect ... was horrible. It started with one silly task. I made my bed every morning. Yup ... huge thing right? For me I woke up at 4:30 and went to work W was always in bed.... shortly after BD she moved out and I left an empty bed in ruins. I made that small change, I made that bed. I started the day with a small but in many ways a huge accomplishment. This snowballed into other things that I incorporated into Cali 2.0 as I changed into a better version. I cut out things I did not like about myself .. replaced them with things I admired in others and to this day I continue to grow.
Moral of the story. True pain creates true change. Seize this time and allow it to make you better.