Normal drinkers don't have problems that arise from their drinking. Normal drinkers don't have withdrawal symptoms when they don't drink for a couple of days. Alcoholism does effect and deteriorate relationships, so is it surprising that someone who admits that they do "over do it"-- has withdrawal symptoms because they didn't drink for 5 days, also has marital problems? No. Do alcoholics often deny their problems and get angry when people stop hiding it for them? Yes. Do alcoholics readily admit they are alcoholics? No.
Sounds like the wife is stepping off the merry-go-round named denial. Hopefully everyone will want to join her. Alcoholism is a progressive disease and a potentially fatal one.