I found a nice quote online:

Life is 10% what happens to you and 90% how you react to it.

I find this to be 100% accurate and I can even go with the percentage to 1% respectively 99%.
I found myself, and a group of people, in a difficult situation and I noticed major differences in perceiving the same difficult situation and making it a negative or positive thing at different people.

How people React to things is precious, and even if you get disappointed by negative behavior, faith in human kind is restored, when you see a different person reacting positive.