What if a friend told you not to tell?

[Jhon]

A friend told me something about another friend that really bothers me, but told me not to tell that he told me.

It bothers me so much, I can't be friends with the person anymore, yet I can't tell them why I no longer want anything to do with them, because I promised that I wouldn't tell.

It makes it really uncomfortable because my former friend is unaware and can't understand why I suddenly won't talk to them anymore, but I can't explain due to my promise.

[mr nood]

that is a tough problem

my advice is to try to get the friend that told you to fess up, they can try to minimize it as a slip up during a conversation or something