The saddest thing about these stories is how the children are treated when they've done nothing wrong. Karina worked tirelessly to gain the affection/approval of her father. She overworked herself. Put herself through more than what most kids would dream of. And her family still ignored her, even downright spited her.
Even I find children somewhat annoying, but no kid deserves that. It doesn't matter how much you dislike a kid, you should treat them right. Even if you don't hit them, this is still wrong - Karina went through so much emotional neglect. And her father thinks she's "acting strangely".
She's not acting strangely. She's realized what you truly think of her, and has decided to stop trying to gain affection she'll never get.