The amazing thing is how long a human body can take that kind of repeated punishment and survive. I have a sister-in-law who is a chronic alcoholic, in her mid-40’s and probably drunk for about 90% of the last 15 years. She has been in the emergency room of the hospital in the community where she “lives” 34x in the last 3 years for injuries that are a consequence of her being drunk (mainly, serious falls). The only call that will not be a surprise is the call with the news that she has finally died as a result of the abuse. At the same time My 81 year old father has a lifelong friend who has been an out of control alcoholic for the past 40 years. Still kicking.
How very sad for your family. When one refuses to admit they have a problem with alcohol or drugs, it is impossible to get them help. Just keep them in prayer - it’s about all you can do.