Addictions come in many forms -- addictions of gluttony, lust, gambling, drink, drugs, tobacco, profanity, even sloth and indolence. Anyone who has really personally struggled with an addiction, or befriended someone who has -- whether it was trying to kick the tobacco habit, conquer alcoholism, or recover from anorexia -- knows the miracle of grace that is involved in deliverance from addiction.
I think we may safely say that that even the most decent and holy of us knows (perhaps better than the rest), even from the small addictions of his soul, what a Catch 22 addictions can be. We wish we didn't have these afflictions; but wishing isn't quite the same as willing; which is precisely the problem, as St. Augustine illustrated so well in his Confessions ("Lord, give me chastity, but ... not yet").
Overcoming an addiction takes more than a single act of resolute willing, or even a series of such acts, even though such resolution is what is dearly desired. Such efforts can be valiant and may be animated by the noblest of intentions; but there is no more tried and true a recipe for disaster than reposing all one's hope in his own efforts. Overcoming addiction requires a recognition of our own helplessness and an acknowledgement of our complete dependence on God. We have to be brought to the point where we recognize our utter powerlessness against it, just as with sin. We cannot overcome it directly.
Therefore we say, at Mass, "Domine, non sum dignus ... sed tantum dic verbo et sanabitur anima mea" ("Lord, I am not worthy ... but only say the word and I shall be healed"). These words are borne up out of an ancient tradition according to which the spiritual healing needed to overcome sin requires resources beyond our natural human reach; and the conditions are no different with addiction. We must be converted. We must be transformed. We must be regenerated. We must be saved.
The trouble is, we cannot save ourselves. So we must learn to call upon the living God who made us; and where we find our efforts at prayer foundering, we must learn to call upon the hosts of heaven for their intercession. "Pray for us!" we cry. Ora pro nobis! Then, in time, if we are earnest and persevere, we find ourselves -- lo and behold! -- healing.