“It takes great personal courage to let yourself appear weak.”
I adore David Foster Wallace. This comes from a chapter in Infinite Jest where he lists the things things you will learn if "by the virtue of charity or the circumstance of desperation" you come to spend time at a substance-recovery facility.
Vulnerability is something I personally find very difficult, but I truly believe it is important in order to grow and learn. Reading this for the first time both encouraged me to make myself vulnerable and also to have real respect for people that do.