Fantasy.

You know how when you were a little kid and you believed in fairy tales, that fantasy of what your life would be, white dress, prince charming who would carry you away to a castle on a hill. You would lie in bed at night and close your eyes and you had complete and utter faith. Santa Claus, the Tooth Fairy, Prince Charming, they were so close you could taste them, but eventually you grow up, one day you open your eyes and the fairy tale disappears. Most people turn to the things and people they can trust. But the thing is its hard to let go of that fairy tale entirely cause almost everyone has that smallest bit of hope, of faith, that one day they will open their eyes and it will come true.

Greys Anatomy