Okay did she die or did she not?

Evidence that she died:

- she drank the poison
- there is no vomit next to her body, so she didn't get the poison out of her.
- She says, "i need to sleep, i need to close my eyes" is that a reference to her death.
- She is completely ignored by teachers and pupils.
- When robert enters the room he reacts like she has died.

Evidence she didn't die:

- robert and another child both see and talk to her.
- she was handed the medicine to make her throw up.
- The film ends with her heading back to London to write another book.

What the hell happened!!??
Please help...