Sometimes, secrets get divulged with the most innocent of motives...during unguarded moments, temporary feelings of security and trust, drunken moments, down moments, sad moments.
Thing is...most often than not, the confidant/confidante also has another close friend or friends to whom most things get relayed. It's just a matter of level of closeness.
And the cycle goes on.
Talking about someone else's secrets scare the hellouta me. So, I don't do it.