Who is Brennan's Mother from Canyons and what is their importance?

Brennan's mother is a single woman who has raised her child alone most of his life. Brennan's mother is desperate to share her life with a man, but all her relationships have ended in heartbreak. Brennan avoids his mother and his home because he does not like to watch her wallow in her depression. However, it is Brennan's mother who introduces him to the man that will change his life. Brennan's life changes when Bill takes him, his mother, and a youth group camping in the same canyon where Coyote Runs died over a hundred years before.