Storytelling in general is a communal act. Throughout human history, people would gather around, whether by the fire or at a tavern, and tell stories. One person would chime in, then another, maybe someone would repeat a story they heard already but with a different spin. It's a collective process.
Normal people have an incredible lack of empathy. They have good emotional empathy, but they don't have much empathy for the autistic kid who is screaming at the baseball game because he can't stand the sensory overload. Or the autistic kid having a meltdown in the school cafeteria because there's too much stimulation.
The negative effects of combat were nightmares, and I'd get jumpy around certain noises and stuff, but you'd have that after a car accident or a bad divorce. Life's filled with trauma. You don't need to go to war to find it it's going to find you. We all deal with it, and the effects go away after awhile. At least they did for me.