almost alcoholic
n. A person who exhibits some of the symptoms or behaviors associated with alcoholism, but who is not a full-blown alcoholic.
Other Forms
Traditionally alcoholism has been understood as a black-and-white condition. Just like it's impossible to be a little bit pregnant, it's long been considered that a person must be either an alcoholic or not an alcoholic. Yet the mood is shifting as various shades of grey emerge and some experts claim that there may be an entire spectrum of possibilities that lie between the non-alcoholic and the alcoholic state.

Welcome to the world of the "almost alcoholic".
—Shelley Bridgeman, “Are you 'almost alcoholic'?,” The New Zealand Herald, December 10, 2013
The almost alcoholic zone is actually quite large. The people who occupy it are not alcoholics. Rather, they are men and women whose drinking habits range from barely qualifying as almost alcoholics to those whose drinking borders on abuse. One thing we do know about them is that the more their drinking correlates with the above statements the more likely they are to drift further into the almost alcoholic zone.
—Joseph Nowinski & Robert Doyle, “Are You Almost Alcoholic? Taking a New Look at an Old Problem,” The Atlantic, April 02, 2012
2001 (earliest)
"As a recovering alcoholic or almost-alcoholic," a senior Bush adviser said, "he really believes in the power of faith to get you through times of trouble."  
—Thomas M. DeFrank, “Bush leads with faith and prayer,” Daily News (New York), May 06, 2001
Fonda has been most memorable working completely against expectation, playing "Klute's" hooker or "The Morning After's" almost-alcoholic actress, or when she's on emotional home turf like "On Golden Pond."
—Sheila Benson, “Movie Review: A Blue-Collar Love Story That Won't Wash,” Los Angeles Times, February 09, 1990