a toxic boy who has a fragile ego and is cocky. He acts nonchalant, however deep down he is hurt and has feelings just like everyone else. He doesn't realize the value of something until he has lost it.

Briefly, "the realization that each random passerby is living a life as vivid and complex as your own." Originally from the Dictionary of Obscure Sorrows, which has a lot more beautiful neologism definitions like this you might enjoy.