Over thought it too much

Do you ever feel interested about something? Do you happen to think about it constantly? What happens when you get too attached to it?
An ordinary girl named Karma was having history class, when suddenly her teacher explained about a tragic event which opened up Karma's mind. She was thinking about it all the time. She heard voices, and imagined stuff all about it. Her friend Ivy was confused about these strange hallucinations and tried to put sense into her.