The Endurance,

I watched the documentary, The Endurance, in the summer. It's about an expedition to the Antarctic in 1914. 28 men, under captain Ernest Shackleton. Their ship The Endurance got caught in the ice and had to survive in some of the harshest conditions in the world. And they did. For 22 months. All 28 of them.
The thing that really stuck with me was that the Captain realized that the most important thing was to keep their spirits alive. As the narrator said, and I am paraphrasing here,
“Anyone can survive on the ice as long as their spirits are strong. Once the spirits are broken, they're dead.”
The most important thing is the human spirit. If we have that, and we work together, we can survive anything. We need, and want, little else.
When the spirit is gone, all the riches in the world can’t replace it.
“There was a presence,” Shackleton had said (again paraphrasing), “Like someone else was there with us.”
Keep the spirit alive.
It’s a matter of survival.