Everyone has their breaking point. If you don't think so, I suggest you do some research.
See" The Red Badge of Courage" a movie with Audi Murphy as the star. Or "To Hell and Back: The Audie Murphy Story". Audi Murphy had great eyes, and could often pick out the enemy in a distant concealed position, which gave him great advantages. He was literally without fear, but he did have the usual recurring nightmares, and other aspects of "Post Tramatic Stress Disorder".
It is well known that the first time in battle, reactions differ. After the first battle, units, and the soldiers in them, get more reliable. They develop an ability to assess the risk associated with various courses of action. That ability to assess risk, and to trust their assessment, often permits experienced soldiers to act when rookies would freeze, still looking for more information. Alas, sometimes the assessment is wrong, because every battle situation is different.
After some time in continuous action, soldiers get tired, and their performance drops. They take short cuts. Some soldiers have the greatest stress when they come out from enemy contact, and then, after a rest, are recommitted.
The bravest man can be stopped by a bullet. The opportunity to fight back gives you something to do, and the directed action takes your mind off the negitive aspects of the battle. The Driver, Gunner, and NCO/Commander all had tasks on which to focus their attention. She was cargo, and had nothing (aside from a good book, perhaps) to contribute. Pretty soon the jeep got into a severe accident, and there wasn't anything else you could do.
Medals are not given as a reward for service, but rather, to encourage appropriate behavior in serving soldiers. Napoleon said "If I had enough ribbon, I could conquer the world." There is nothing we can do to reward a soldier who is killed in action. He is above our praise, and free from all worries and cares. Still, medals given to those wounded, killed, or successful, can be awarded as an indication that the Service finds their example useful.
When Jessica said to the Rangers, "I am an American Soldier too" that was a wonderful example, to my way of thinking. Your mileage may differ.