Cardiomyopathy means dysfunction of the heart muscle which can be due to many different causes including alcohol. So the recommendation for patients with alcohol related cardiomyopathy is to quit drinking altogether.

Can make it worse or cause it.

Cardiomyopathy is weakness of the heart muscle. Can have many causes coronary artery disease, hypertension or alcohol. Many studies showed a clear relation of lifetime alcohol consumption to structural and functional myocardial and skeletal muscle abnormalities in alcoholics. The amount of consumed alcohol was large—the equivalent of >80 g alcohol/day for 20 years. Further evidence came from data on acute alcohol effects. In alcoholic
cardiomyopathy, dilation and impaired contraction of the left or both ventricles is observed

Yes there’s an entity known alcoholic cardiomyopathy. Go easy on the alcohol

Alcohol has an effect on the heart muscle. Again, it's the quantity & frequency.

Heavy drinking over time can affect the heart muscle as it does to other organs like the liver. If you have underlying heart issues for other reasons, that could make the situation worse. It is best to drink in moderation or not at all.