What is a theme of Touching Spirit Bear and textual evidence that explains the theme?

One of the book’s themes is that you must forgive yourself in order to move on with your life. 

Cole was a very angry kid.  His anger was a result of self-loathing.  His parents were both negligent and abusive.  His father hit him and his mother was an alcoholic who did not seem to care what happened to her son.  Cole turned his anger outward, trying to rob a hardware store and attacking his classmate Peter. 

Garvey explains to Cole that Circle Justice is harder than jail time in some ways, because a person has to change.

Everybody is a part of the healing, including people from the community—anybody who cares. But healing is much harder than standard punishment. Healing requires taking responsibility for your actions.” (Ch. 1)

Circle Justice did not seem to be doing Cole any good at first.  They left him on an island for introspection, but instead he tried to escape, burned down his cabin, and attacked a bear.  It was a turning point for Cole when the Spirit Bear almost mauled him to death.  Part of the long road to recovering was coming to an understanding that he was one small part of the world, and only he could forgive himself.

Peter is an important part of Cole’s journey.  Even if Cole can’t forgive Peter and Peter can’t forgive Cole, understanding why he did what he did to Peter is an important part of Cole’s path to success.

“I don’t care if he forgives me.”

Garvey rubbed the back of his neck, then glanced up toward the ceiling. “How come everything is always about you? This forgiveness isn’t for you. Until Peter forgives you, he won’t heal.” (Ch. 3) 

Cole becomes a different person when he returns to the island.  This time he actually tries to introspect.  He follows advice, including exercises like soaking in a spring and carrying a heavy rock up a hill.  It is through his time in nature that Cole learns to forgive himself. 

When Peter arrives on the island, it is hard for him to be around Cole at first.  The boys never become friends, but they do come to an understanding.  Peter realizes that Cole is not the boy he once was.  Seeing this in Peter, Cole makes a full transformation into a much less angry person.