Nietzsche said “that which doesn't kill us, makes us stronger.” Little did anyone know at the time that those words have a powerful psychological basis.
Everyday we hear about trauma. About people surviving horrible tragedy to themselves and to their loved ones. And we all wonder how do they go forward. We know for example that the incidence of divorce, after the death of a child, is well over 50%.
We know that the trauma of war and combat can take years, if not decades, to come to grips with. We see the horrors of genocide, tragedies like 9/11 and Oklahoma City and we wonder how to people cope and why, even in the face of such horror, so some people thrive and come out stronger.
Or in the words of Hemingway, “the world breaks everyone, and afterwards some are stronger in broken places.”