Question regarding the PTSD Cup analogy.

boppy sprite

There's a section I was hoping someone might be able to expand upon. Specifically:

"When military are trained, they're trained to have some PTSD symptoms, especially Army, Marines, or Special Forces-type training. Hyper-vigilance, startle response, alertness -- these are all symptoms of PTSD. When leaving the military and without combat, this training quickly subsides and the person reverts to civilian behavior.

Once a soldier enters a combat zone the brain accepts that this training saved their life, or their buddy's life. This makes training a priority for survival. The training becomes instinctual, regardless of whether they are in a combat zone, or not. This block is one of the most difficult to lessen, and typically only diminishes from a combination of time, and decreasing the traumatic effect."

I remember the soldiers screaming through the megaphones: dance, dance for your life. Get up to the roof or you will die.

How does one go about decreasing the traumatic effect? Exposure therapy? EMDR? Little confused here and it feels like I'm missing something obvious.
I can only speak about myself. My husband is a veteran. Was in war zones. I have ptsd from almost dying from bacterial meningitis of my brain. I work on me my thoughts poly vagal theory so I minimize my fight flight fear fawn responses. My husband has shtf beliefs from combat following news world events for years. In 2020 when we met- 4 months into the pandemic- his behaviors as far as hypervigilance not sleeping stress etc increased. Trauma is embedded in the nervous system. The only treatment he had was another veteran telling him to throw his memories in the trash. If only it were that simple. I have had to accept he will always be this way. I have to change. I am worried for him though. I have found research that indicates the more the brain is flooded with dopamine the thinner the cortex/ pre frontal cortex becomes decreasing focus on life sustaining behaviors and goals.