You go out with a girl you used to date, she looks so damn good, and then at a certain point you say, Boy, now I remember. I know why I left!
Fantasies are more than substitutes for unpleasant reality; they are also dress rehearsals, plans. All acts performed in the world begin in the imagination.
There is only one way to happiness and that is to cease worrying about things which are beyond the power of our will.