My family and very close friends know - I don't discuss at length but they're aware that this forum exists and why I'm on it.
Also from time to time I have friends who are hitting a bottom and start talking about how they no longer want to drink/use/what have you - I do my best to explain this forum and encourage them to read through it even if they don't join (my hopes are that they do) and normally send them the link and tell them how much I understand (I don't declare alcoholism from the rooftops - but I do admit in private to those that need to know they are not alone)