Hi! I believe I can be of help with this issue.
First, let me say I can imagine how difficult this situation must be for everyone. On the one hand you are young and they represent for you one of the few links you have to family, to not being completely on your own in the world. On the other hand, you know that they are being self destructive with this alcoholism.
And this is actually the key to my answer to you that you need to think about and consider seriously. My focus here in my answer is going to be on you. Why?
Because you are very correct that you will not convince them to change their ways. And it's not just because you're 20 years old. Even if you were 40 or 60 you would not be able to convince them. This is a reality of alcoholism and of most addictions. Not you nor anyone else in their family can make them leave the bottle until they are ready to face it themselves. This is the reality you have to accept as the starting point. Okay?
You are clearly a good-hearted person and you very much want to help them. My concern, though, is about something called enabling. You can Google this and learn about it. Enabling is where you try to help, but wind up actually enabling them to stay an alcoholic. This can happen without realizing it.
Therefore, to have a relationship with them without having it become an enabling relationship or without becoming disenchanted and angry with the person, I recommend that you look into joining Al Anon. That's the part of Alcoholics Anonymous that is for the family. Here’s the meeting finder:
Not all meetings are the same. So if you don't hit it off with one group, find out where there's a different meeting. And they have written materials that can be very helpful to you both in how to have a relationship and how to encourage someone to seek help in a way that has most chance of them actually listening.
So, try to have a relationship with them. But don't do it without first being educated and having support. Okay, I wish you the very, very best!
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