Friedrich Nietzsche : "What doesn't kill us makes us stronger". It doe not makes us physically stronger. Things that almost kill us definitely take something from us. It could be something physical or something mental or both. But our organism is very coping. It compensates the loss with what is left. So retained parts become much more developed and thus stronger. Those parts are stronger than they were before. But because there are missing parts, the compensation does not make you whole again. And definitely you are not what you are used to be.