Im happy this generated a discussion.
I think a lot of people have great points. I'll expand on why I say the stomach thing.
When I meet new people they sometimes ask why I don't drink, they sometimes dont. I usually don't offer any info unless asked but if pressed I say I have a bad stomach. Truth is, I have a host of chronic conditions which mean that I shouldnt drink, have caffeine, or eat spicy food in anything other than moderation. But thats not why I dont drink.
In my opinion telling people I have a problem with alcohol opens the door for further discussion that Idont want to have with strangers.
I hope a new person reading this thread gets some good ideas as I think this question is a hard one in your early recovery so kudos to everyone who answered!
Oh and I'll add if someone kept pestering me I'd cut them out of my life quick, I've found that has never happened once I've said I don't drink.