Because every thought she had, everything she observed around her, every conversation, every experience, everything that made her laugh - she imagined telling him, or him watching. She wanted herself, the particular way he saw her and the way she like to be seen by him, reflected back, over and over. It was like there was this letter to him in her head that she was always writing and never getting to send. It reminded her of being a kid and making a new best friend, how the two of you made your own world with just that person, and never wanted to leave it. And though she'd never been in love, it reminded her of that, too.