Damn, man. Many methods of "morale-breaking" I have seen in manga, but this one is probably the closest one that I feel really tangible, really hitting the feels. Confined inside basically a void null space, fed with only the most basic of food, your senses basically stop functioning and it'll be hard to taste or smell anything. For all you know, the only thing you are hearing is the beating of your own breath and heart.
And fed with daily barrage of misinformation from the only channel you have to the outside world. You know this channel is not to be trusted, but to satisfy the basic craving of connecting to the outside world, what other choice you have? Deny the lies and maintain your isolation in the darkness, or accept the lies, even though the light at the end of the tunnel is from a train that will take your life away?
What even is living?