In Night, when did Wiesel and the others finally let hope die?

Nowhere is the exact time or incident that produced the
death of hope in the protagonist precisely referenced. However it is absolutely clear
that there are a number of key, foundational moments which produce this death of hope in
the protagonist. Of course, everyone reacted differently to the horrors of the
concentration camp and people would have let their hope die at different times. However,
one of these moments for Elie is definitely when he and the rest of the camp is forced
to witness the hanging of three prisoners, one of them a young
boy:

And so
he remained for more than half an hour, lingering between life and death, writhing
before our eyes. And we were forced to look at him at close range. He was still alive
when I passed him. His tongue was still red, his eyes not yet
extinguished.

Behind me, I heard the same man
asking:

"For God's sake, where is
God?"

And from within me, I heard the
answer:

"Where He is? This is where--hanging here from this
gallows..."

That night, the soup tasted of
corpses.

This moment can be
identified as the moment when Elie lost his faith forever in a God who could allow such
atrocities to be committed, and implicitly we can identify the death of his hope. Of
course, this is one of many possible moments that you could identify so you would do
well to go through the text by yourself and pick out other similar moments that result
in the death of hope in Elie.