early in my recovery in certain scenarios i would tell people i'm buddhist and have taken the precept to refrain from intoxicants. while this is technically true it seemed to be an ego thing for me so i quit saying it. now i'll say i don't drink to strangers and i'm a recovering alcoholic to people i know.
i've been very upfront with the people in my life about what i'm doing and it's rare that i'm in situations with strangers where drinks are offered or the question arises.