Growing up with an alcoholic father and a mother that disappears for weeks at a time can change a person. And by changing them, I don't mean for the better.
Because Christopher grew up around alcohol, and even drugs, he became addicted by the age of 14. He never really had friends in school so he never really knew how other families worked, he believed the way he lived was normal. Sure, he saw families on television but he never for one second thought that was how things were with some people.
Although Chris has trouble with certain substances, the thing that helped him the most was music. Listening to it, playing it, creating it. It keeps him sane, well as sane as he can be.
That's all he had. Alcohol, cigarettes, drugs, and music. Until a girl named Naycee came along.