The life that the characters experienced in this sober narrative can't really be described as much of a "life" at all. The text makes it clear that their lives consisted of hard, exhausting labour combined with very low amounts of food and above all the constant fear of death and punishment. If we remember what the German officer told them on their very first morning about what is expected of them, we can see that they are expected to behave more like slaves or robots than anything else:
"You will have discipline," he said suddenly, without preamble. "You will work hard. You will never answer back, complain, or question. You will not try to escape. You will do this for the Fatherland. You will do it--or you will die."
The characters find this change in their fortunes incredibly hard to accept, and have to work hard to keep their spirits up and to continue trying to find the will to live in the face of such brutality and constant fear.