A crush occurs when a person observes another person whom they find attractive, and forms an idealized image of the person in their head. The person then "falls in love" with this image, which may have no relation to the real person whatsoever. A crush is an inherently unstable condition. The crush is likely to reject the advances of the afflicted person, because they may consciously or unconsciously realize that the afflicted is in love with an fictional image, not them, and that they are not compatible despite the afflicted one's daydreams. Alternately, the afflicted may get to know their crush well enough to realize that they are in love with a fiction, and become disillusioned. A happy ending is also possible: if the daydream image actually resembles the real person closely enough, that might be referred to as "love at first sight". "True love" must involve an understanding of a person on a fundamental level, which is unlikely to reside in the fantasy of a crush unless one postulates an empathic connection or accepts Plato's concept of God-given right opinion.
Crush is an album by Bon Jovi.
Crush is a movie featuring Andie MacDowell.