Earlier quoted context omitted.
So your recipe for, "emotional success" is to not be affected by other people? Got it.
Is it really wrong though? Making your emotional state dependent on others is a terrible thing to do to yourself, because people can be fickle and change. Emotional independence is tremendously helpful for emotional well-being.
"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. The only place outside Heaven where you can be perfectly safe from all the dangers and perturbations of love is Hell."
- C.S. Lewis, The Four Loves
Yeah, you can get hurt. For sure, be wise about who you become emotionally dependent on. But not having your emotions entangled with another's is to miss one of the great joys of being alive.