I think you are powerless in the sense that ultimately it's his decision to address the disease or not, but honestly I don't know any alcoholics that actually did this with sucess on their own without any sort of intervention. I think being involved with an addict is sort of an "all or nothing" commitment. Either you agree to accept the addiction, or you don't and cut off ties until that person is clean. I think help should be offered but only when the person is committed to coming clean, because if not then "help" generally becomes "enabling" and the addict is treating you like a doormat. I have two uncle's on my dad's side that are acoholics and even though my parents are not, that is close enough for me to avoid all drinking save for a margarita or frozen lemonade drink once a month. By nature I am not a very patient person, I simply will not sit by and allow someone to self destruct or engage in any behavior that might push me along the same path if it's something that runs in families. My family tried an intervention with one of my uncle's and it didn't work, but go figure they still invite him to family gatherings, help him with this or that, etc. Maybe it is harsh, but to me he is more like an acquaintance than family. I keep my distance for a reason and maybe that makes me a stone cold bitch but until he shows us that *he* is the one with the problem and wants to get help then he can stay out of my life.
I had a similar experience involving anorexia. I knew this girl, and was closer friends with some of her friends, and the way that they "helped" her (by basically defending her, trying to be all hush-hush, not hurt her feelings etc) made me lose a lot of respect for them and not want to be friends. Being nice doesn't save someone's life, unfortunately. It went on for so long she was literally a pound or two between life and death, and one of her best friends came to me and said she wanted to move out and move in with me because her friend was doing nothing to address her anorexia and was refusing help and it would not be on her watch that she had a heart attack and died. If this anorexic person had been under 18 years old I would have called protective services because her family's denial was IMO downright neglect.

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