Hi
Your post just reminded me of my sister. She has the same history as your friend but has been drinking for 20yrs now. Over the years she has become worse & worse. Over these years nothing you could say would stop this horrible addiction. She has lost everything!
I did the same, was there for her, went away from her, helped her again, stayed away again and now I really dont know whether she will every want to stop.
To keep my sanity, I have to keep my distance otherwise this just encourages her bad behaviour.
True, you wont stop him drinking but I believe just letting him know that he will have someone to go to if needed, is good.
If I call my sister to see if shes ok, she cries, because she cant believe I still care. (thats what she calls it). I will always care and it kills me to see what she has become. I accept it is her life but to be honest I find it difficult to accept she may die, therefore, I let her know I love her.
Be there in spirit for your friend but I would advise not to assist financially or otherwise.
Best Wishes JJ