From C.S. Lewis' Four Loves:
"There is no safe investment. 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 it intact, you
must give your heart to no one, not even to an animal. Wrap it carefully
round with hobbies and little luxuries; avoid all entanglements; lock
it up safe in the casket or coffin of your selfishness. But in that
casket—safe, dark, motionless, airless—it will change. It will not be
broken; it will become unbreakable, impenetrable, irredeemable. The
alternative to tragedy, or at least to the risk of tragedy, is
damnation."