Brian in the beginning is very depressed and shows that his life is terrible. Woe is him. He is torn apart because of what he knows ( the Secret ) and this is a major weight on him. The secret overwhelms him so much that when the pilot dies he does nothing for awhile.
Brian's first sign of maturity is when he successfully pilots the plane, but he showed how weak he was when he freaked out when he lost signal with who ever was on the communication radio. he was very negative the first few days he was in the Canadian shield.
After the incident where the plane flew over Brian and he tried to commit suicide he believes that now he has tough hope, and he no longer believes he will be rescued. He now is okay in the wild , and has more self confidence. His new found tough hope has blossomed in him and pushed out his despair. He now is truly a man.
No more self pity. Only me in the wild.
He was very uncomfortable when he found the survival kit and he showed that unlike in the beginning of the novel he now is strong and doesn't need any help from supplies or from others. He is now independent and free from the secret.
Brian grew to love his home and was sad to leave his life changing environment but he knew he was lucky to survive. He has learned lessons he will never forget and he will never be the same depressed person he once was.