Sorry to know that. Your niece must be bothered about her father's health. Alcohol brings suffering to the family more than the individual.My brother is still addicted to alcohol which my niece keeps worrying about. You are lucky that he realizes that he has to do away with his addiction which my brother doesn't.
My husband is a health freak. He is very particular about his diet, exercise etc. He takes drinks on Friday night and in social gatherings. Recently, he has crossed his tolerance limit at certain occasions and that was not good. He has a bad hangover later and was pretty guilty. Good that he realises it and wants to cut down on that too