When emotions run high, I so badly want to file for D.
That is your primitive lizard brain having an anxious knee-jerk reaction. Sadly the lizard brain is always gonna be much faster than your adult brain. The only way out of it is to learn to go slow and be mindful. In the beginning your body will feel anxiety of it (awaiting for beasts to kill you) but it is like a muscle - with discipline and few months of repeat you can reach a state where you can act with sanity and detachment without anxiety. It is good place to be.
Not sure if you are familiar with mindfulness, but it can be really helpful as "cheat sheet" to fight off lizard brain. For example one thing that worked for me was "counting to five" before responding. Another success for me was rule of three - before making any major decision, I paused for 3 minutes, then 3 hours, then 3 days, weeks and ultimately months. It did a world of difference, and often times I discovered major faults in my original thinking. Time is your friend, use it wisely.
You might also check various breathing techniques. They help controlling physical anxiety, which is part of reason why your lizard brain is so reactive.
There is lot you can learn of yourself. And it is not for her or your marriage, but for you and people around you. When you learn about this stuff, it will make your life better day after day for rest of your life, regardless of what happens with your marriage.
Sorry for pouring more "new stuff to learn" for you, LOL.
Alvin
At time of BD.... Me: 43, XW: 41
Kids: G19,G18,G14,G12,S5
Together - 20½ Years, Married 19 Years
BD ("I don't love you"): Feb 2019,
BD2 ("I don't want to fix this marriage."), Mar 2020
D filed May 2020, D finalized Dec 2020
I have moved on, and am in new relationship.
Lessons from Stoicism and REBT helped me to exit the chaos zone and become a better person.
"Happiness and freedom begin with a clear understanding of one principle: Some things are within our control, and some things are not. - Epictetus"