Your mileage may differ, as the saying goes. Here are a few: insomnia, irritability, depression, lack / loss of purpose, etcetera . This sums up one experience:
He lost his temper over small things like a door banging or a dog barking. And he’d go to bed for days on end.
https://tvblackbox.com.au/page/2023/09/11/unbreakable-dean-yates-discusses-journey-to-healing-on-australian-story/
During Desert Storm i experienced similar symptoms due to sleep deprivation; I wanted to pummel my friends for chewing too loud. I mean this irrational rage would overcome me. The others felt the same.
Read more about a famous war reporter, Dean Yates, and his moral injury here: