Remember the D-Day Dodgers from sunny Italy? The Eighth Army.
Away in the sand pit for three years without a single break, their reward was the invasion of Sicily followed by the Invasion of Italy and the advance upon Rome, fighting every inch of the way. For most of them it was five years away from home fighting with shortages of food, ammunition and in many cases with obsolete equipment. They came home fit, sane (mostly - Spike Milligan is an obvious exception) and randy and got on with the rest of their lives without counselling or help. Millions of their comrades in arms - and their enemies too - went through the same without cracking up. Are the 'psychological effects of overstretch' a bit over-stretched perhaps?