Once upon a time there was a girl. She was an unremarkable girl, just like any girl you might meet. But she was a sensitive girl, and the world was harsh and corroded her.
One day, the girl was in a terrible car accident and shards of glass and gravel ground into her face. The skin would heal, the doctors said, but there was nothing they could do to save her eyes.
Of course the girl was very upset at first. But then she realized that blindness was better: she'd never have to deal with seeing the ugly things in the world- abuse, blood, or people constantly giving each other the finger in the streets. Things she couldn't see no longer existed to her.
Only pretty things were in her head. It was calm and serene, except when broken by the noises of the world.
A few years later, the girl was standing near a bunch of fireworks when somehow someone set them all off. The girl was much too close and again had to go to the hospital. Her burns would again heal, but this time her hearing was beyond repair.
As soon as the girl realized that she had become deaf, a small pocket of joy seemed to light her up. Now she couldn't hear the arguing and cussing and put-downs. These things stopped existing to her, too. The only things that were left in her mind were what she put there, and her inner reality was clean and perfect.
Over time, though, the girl began to run out of nice things to put into her head that weren't already there. Her inhumanly sweet friends had become dull. In the creation of an impossibly nice world, she had forgone human contact, as awful as much of it was, and so her only companion was herself.