i think its about some guy she doesn't know well but she has strong feelings for and imagines him to be the perfect guy. she's attracted to him but all she knows is who is so she wants to know him better. she was too afraid and shy to talk to him and when she finally mustered up the courage to do so she saw him with another woman. Because she spent so much energy imagining how great it would be to be with him, she has to force herself to stop thinking about him when they really didn't have anything in the first place. its a crazy heart wrenching crush.