How it Works.

"It is plain that a life which includes deep resentment
leads only to futility and unhappiness. To the precise
extent that we permit these, do we squander the hours
that might have been worth while. But with the alcoholic,
whose hope is the maintenance and growth of a
spiritual experience, this business of resentment is
infinitely grave. We found that it is fatal. For when
harboring such feeling we shut ourselves off from the
sunlight of the Spirit. The insanity of alcohol returns
and we drink again. And with us, to drink is to die."

From the book Alcoholics Anonymous.
Page 66, Third Edition.