Wikipedia has this translation of Nietzsche's original line:
"From life's school of war: what does not kill me makes me stronger."
Today it was in the news because it showed up in an email of Hillary Clinton's:
"Well, what doesn’t kill you, makes you stronger (as I have rationalized for years), so just survive and you’ll have triumphed!"
The linked article describes her as quoting Kelly Clarkson's pop song version of Nietzsche's aphorism.
I'm inclined to question generalizations, and so whenever I hear this one I think that it's not always true.
Some harms may leave you weaker,
Leave your life a little bleaker.
And, I wonder if that's what she was thinking when she added that she had "rationalized", which I take to be a self-deprecating remark about her own mental practices.
In her own life, she seems to have done a lot more than "just surviving". She's rich, famous, powerful.
On the other hand, she is not universally loved. She is the steady recipient of scorn and ridicule from her many enemies. And even her friends speak delicately of her relationship to truth-telling.
Of course, truth-telling is not a typical stand-out trait of politicians or diplomats, who tend to use words pragmatically, as slippery tools to score points.
Politicians often feel
A tenuous grasp to what is real,
Especially if, to reach their goal,
They've auctioned off their youthful soul.