1. Extreme narcissism
2. Condition in which persons are literally in love with themselves and/or are primarily attracted to qualities in others that they themselves possess.
3. Mental state in which one's perception of reality is warped by self-obsession. The world exists only as a reflection of the self.
Also: One who places unusually high value on one's own opinions, appearance, and personality.
Paris Hilton is so self-gay she can't conceive of a guy who wouldn't want to sleep with her or a girl who wouldn't want to be her.