Chronic alcoholism could contribute to impairment of nerve system and brain functions, even some psychiatric disorder such as hallucination, heteroptics, acousma and so on.
In the patients with chronic alcoholism caused by lastingly drinking high degree wine,54% had hepatomegaly and liver parenchyma showed lipoidal-change acoustic image at varied degree.
Of course, many other life factors can lead to infidelity; from unresolved emotional issues, baggage from past relationships and... excessive alcohol intoxication.