Proven by science: couples that share the same drinking habits actually tend to stay together, except when both are heavy drinkers:
Researchers reviewing data collected from 19,977 married couples in one county in Norway reported that spouses who consume about the same amount of alcohol were less likely to divorce than pairs where one partner is a heavy drinker and the other is not — especially when the wife is the one doing the drinking. [...]
They found that divorce was generally more common in couples with high rates of alcohol consumption, but that the highest divorce rates were found in couples where only the woman was a heavy drinker. Among couples where the wife reported being a heavy drinker (a measure that including admission of an indication of "hazardous drinking") and the husband a light drinker, the divorce rate was 26.8%; when the positions were switched and the husband was the heavy drinker, the divorce rate was 13.1%.
In couples where both members were heavy drinkers, the divorce rate was 17.2%.