I have read french letters to their family from the trenches of the first world war. I have read accounts of the sailors that were part of the sailor uprising in Kiel in 1918. I have read the accounts of german soldiers of both Wehrmacht and Volkssturm from the second World War, the former from early in the war as well as from Stalingrad, the latter from the end of the war. I have listened to the translation of some accounts of the Himeyuri during and after a war.
Let me tell you one thing: It is not only perfectly normal for anxiety of the telling person to end in their written text and tales, it seems to be pretty much impossible not to be anxious about the coming battle if it is clear on the horizon. Some soldiers or kids doing duty for the military might be bored out in a fashion that they coldly look into the future, but most will fear for their life in some way or another. Let me toss together a pair of examples of some soldiers' behaviors based on one french letter from WW1.
A young soldier hung his bread bag to the boot of a Boche1 soldier that died next to the trench, the stiff limb sticking into the muddy bulwark. "Hey Corporal Francois, the Alboche1 is serving us tonight!" Felix yelled over to his commander, a grin on his face. Quite some of his comrades joined laughing, throwing a few insults towards the german trenches so close through the no-mans-land.
With a sigh, the Corporal eyed up at the sudden interruption to his letter, giving the young Soldat deuxieme and his fellows a glare. How could he laugh about the misery of the dead one? Just a mile back, the land where once cabbage and leek had been planted had been turned into a field that only grew bottles turned upside down, the papers of each fallen comrade in them. Were they just trying to mask their own anxiety about the upcoming engagement he had just tomorrow he had just gotten orders for or had the months in the trenches turned their humor down this morbid way? Oh how he longed for the time they were promised to rest and recuperate their morale but which had been rescheduled again and again...
1 - Boche/Les Alboches is a typical french insult for Germans in WW1, stemming from allemand (French for German) and caboche (slang for head). It also meant pretty much barbarian