I am sure that you have already tried lots of things in order to try to help your family member with what sounds like alcohol abuse. This article may help with talking to them. https://www.healthline.com/health/most-important-things-you-can-do-help-alcoholic#approach Liver issues are just one way that alcohol abuse shows. When you drink alcohol, you are consuming water, ethanol (drinking alcohol), and things like sugars and fats, depending on what’s mixed into your drink. Your body can store sugar, fat, and water, but it has no way to deal with alcohol other than to filter it out. When alcohol gets into your bloodstream, your body essentially treats it like poison and prioritizes processing it.
Your body works to process alcohol first so that other things like the water and sugar may go to storage, causing water retention. Fluids start to collect in your body tissue, and gravity makes water collect in your feet and sometimes your hands. Cardio myopathy is another issue. Alcoholism can also cause a condition called cardiomyopathy, which is damage to your heart, causing it to stretch and weaken over time. A weak heart struggles to pump blood throughout the body, and fluids can leak into your body tissues. A common symptom of this problem is swelling hands and feet.
With relation to diabetes, he can do blood work to find out. https://www.webmd.com/diabetes/type-2-diabetes
Has your doctor suggested greatly reducing your wine consumption? That's a lot of sugar, and a lot of alcohol, for anyone to consume daily.