they will not tell you that they shared your secret, but you will find out. It is impossible to tell these people anything in confidence because they will twist your information and relay it onto whoever gives a shit. share bears ruin friendships.
Person B: AHAHAH he is so clueless
Person B: Yo justin, you are a dumb shit
Justin: what the hell? How did you find out?
Justin: I'm sorry I'm such an idiot
Person A: Fucking Person B is such a share bear