SD, Use your head not your heart. One of the best lessons I learned in the military was to deal with what I could control and be prepared for the "what ifs." Quit reacting to her.
Another piece of my military training that helped was my POW training, not kidding. You are in a incredibly stressful situation and are very much on your own. You have to make goals for yourself, think thru a plan to achieve them then execute. Then when you get on your game you start having fun doing it. I used the Stockdale Paradox to help me plan. Another poster, SmileyPerson, likens DBing to what he calls the Spiers Doctrine from Band of Brothers. Capt Speirs tells Blthye you can't become a good soldier until you realize you are dead. You are already divorced, think thru it.
Cheers
ps Everybody screws up. It's how you bounce back that matters.
M22,H45,W45 S21/18D12 Retain faith that you will prevail in the end, regardless of the difficulties and at the same time confront the most brutal facts of your current reality, whatever they might be.