Main Character finding out about his real mother from Jacob and then losing the only real family he every had known. Now it was up to him to save the Academy at all costs and not let anyone know what was happing. Only others that knew about what he was doing was Jacob and Arthur.
He knew no matter what. That he couldn't let Samantha, Haley, Lily, or anyone know what he had been doing sense the first semester now. If others knew that he was trying to do everything to save the Academy. Including Samantha. That they want to help. That is why main Character didn't tell Samantha anything.