Hello there, so, I will say I would rather be called a "Secret Keeper" because I respect people's secret as much as I respect my own self. I think being confided on by someone else who is not me means the person trust me to hold a key to part of his his or her life, so why on earth will I spill the beans when I know very well it will betray the trust they have on me?.
However, when secret becomes a burden, then it is no longer a secret to me. There are situations that some secrets becomes a pain on the neck, somehow it could even go as far as messing with our peace of mind. There are some secrets that can put us into trouble if we can't let it out of the bag, this is not just about being tagged a betrayer, it's about making sure your sanity and safety is still intact.
So, in a case where my friend confides in me to keep a gravy secret which inturn will ruin someone else's life is a No to me, I will sure spill it out as long as everyone gets to stay alive, whatever might have caused situations that wanted to ruin someone's life will be sorted out in the possible future.
Don't get me wrong, I can keep secret but then, I can't kill someone directly or indirectly by keeping such secret. Everyone deserves to live and we just can't get to end their lives untimely just because of a flimsy secret that can save them from going 6ft beneath the earth surface, it doesn't worth keeping.
Also, if I get to keep this kind of secret, then the other person gets ruined or screwed up or even lot their lives, I will forever live in regret and endless guilt, so why should I trade my own peace of mind and sanity to just some mere words I could utter and save a soul from such damnation.
Whatever makes a friend think confiding in me to keep a deadly secret as that would prove to him or her that I am a good friend, then I rather be seen as a bad friend because, definitely, I will be spilling it out, I can't be that hypocritical at someone's expense of life, it is never done that way, secrets are meant to be kept and lives are meant to saved, this is what humanity is all about.
In conclusion, a secret should be kept but let's not allow it cross the boundary of humanity, it won't be worth it, spill the beans and save a life, hypocrisy is never a good attitude, it is better to be judged by 12 than carried by 6.