In the book thief how does Markus Zusak show that despite intense suffering the human spirit endures?

I think much of this has to do with the relationships that they form and a sense of hope for a better day. Even though Liesel must leave her mother, she has a new family in Hans and Rose Hubermann. Liesel also meets other people like Max and Rudy. These relationships form a bond and a will to endure and live. Even Death marvels at the resilience of these people.