Too much. It's too much. She's had enough. All her "friends" telling her that they care, but none of them really showing it. The only real friends she has existing online, people she's never even met, and never will meet.
And no one understands. No one even tries to understand, because no one wants to. She's just insignificant, unimportant, un-noticed. The only thing she's able to think about is how much no one would care if she just disappeared.
It would take them a long time to realize she had gone. They probably wouldn't even miss her. None of them. They wouldn't even realize what had happened.
She had to leave. She didn't want to feel like that anymore. So she made up her mind.
Without even writing a note, she packed a small bag with a change of clothes, a few books, and some food she stole from the kitchen. And then she left. It didn't matter where she was going; she just had to get away. She had to find someone someplace that would care about her.
She didn't get very far before she changed her mind. She left her bag in the park near her house and continued walking. Soon, she was standing on a bridge over a small river, looking down at the water below.
With tears streaming down her face, she looked back once in the direction of her home. "I'm sorry," she whispered, and then she was gone, lost under the murky brown water forever.