She had no friends even as a kid when her parents were still alive so I assume it's not all an act or a trait of personality developed later. No doubt she changed dramatically as well, though, anybody probably would.
She also said she intends to continue her parents work and apparently they were well known around the world for whatever research they did so all the studying is of course explained by that, even if it is quite a decision made by a little girl.
One thing I wonder is who took care of her. Surely she didn't live all by herself right from the beginning. She wasn't very old when the accident happened. There had to be someone.