Matt, I have been following your posts for a long time, and meaning to post everytime there was correlation to my situation. So that would have been many many times.
I can only advise at this stage to let go, and go with the flow.
It reminds me of the Serenity Prayer adopted by AA
Like you, I wound myself up, as to the why's and wherefores as to why this was happening to me, to the extent I had a heartattack.
I now look back, and know my wife was not worth it, does not deserve headspace for what she has done to my kids and me. I am so much better off without her, and you will get there oneday. The quicker route is letting go.