Bisexual Awakening
When an individual, who has always thought or assumed they're straight, suddenly develops a huge crush on someone of the same gender. This makes the individual wonder if they are actually bisexual, rather than straight. As the same-sex crushes persist (as well as opposite-sex crushes), they realize in time that they have had their bisexual awakening, and are indeed a bisexual.
"It's weird... I've always only ever liked girls... but now I have the biggest crush on Matt! I want him, I want nobody but him! I've never felt this way before!! I... think I've had my bisexual awakening!!"