What do you think about me exposing a frat brother?
What made you decide to expose him?
He was acting like a jerk to me, treated me like dirt.
I guess it depends on how big the secret is. If they trusted you with it, you should not use it as ammunition to hurt them later.
That's not the way I see it.
It's wrong to tell a secret that you were trusted with, unless that secret involves someone being hurt in someway.