All my friends know that I'm using different kinds of drugs for several years, and that's part of my lifestyle. I mean, they wouldn't be "friends" for me if they just ignore something that managed to get such a place in my life. Basically, everyone I meet and talk a bit with is likely to discover it quite quickly, 'cause it's not something I'm hiding or I'm ashamed of. Of course, I speak more freely and extensively about drugs with those of my friends who also use - a large amount of them, actually.
My family is reduced to a very few people. My mother is the only one aware of my drug use (she knows the broad outlines, not all details about substances, quantities, frequency ...), partly because she was the privileged witness of my adolescence and my early adulthood, but mostly because even though she disapproved, get worried and still does not understand what I'm looking for into drugs, she finally accepted it and trusts my judgment.
During my studies and my professional life, I try to be discreet about my private life.