Think he has no faults? Blush when he walks by? You are infatuated. When you are infatuated, your crush is so severe that it's pretty darned foolish.
Infatuation comes from the Latin infature which means "to make a fool of." You can be infatuated with a person, but you can also be infatuated with an idea: "Nick was so infatuated with the idea of knighthood that he wore a suit of armor to the prom, and asked to be called 'Sir Nicholas the Brave.'"