I told very few people myself, only the people closest to me and who I could count on for support without scrutinization.  I told them upfront, that it was a personal decision, I am telling you because I trust you to support me through the good and bad.  I don't need a hawk watching over me, but if I ask for that, I know they'll be there.  My sons are actually the worst for that, they watch everything I eat and say, should you be having that?  Not so much now that I am banded, because I am on the strictest of diets.  Sometimes you need that, sometimes you don't. 
I would chose to tell the people who will support you no matter what. 
Best of luck! Cathy