Love

"To love at all is to be vulnerable. Love anything, and your heart will certainly be wrung and possibly be broken. If you want to make sure of keeping you heart intact, you must give your heart to no one. Wrap it carefully with hobbies and little luxuries; avoid all entanglements; lock it up safe in a casket of your own selfishness. There it will not be broken: it will become unbreakable, impenetrable, irredeemable."
C. S. Lewis