You can stop being friends with someone and still keep their secrets. That’s character.

What someone told you was given in confidence, and the confidence was not a term of the friendship continuing. The end of a friendship often comes with a temptation to treat the stored information as yours now. Using it is the one move that makes an ordinary ending into something else. Keeping it costs nothing and nobody applauds.

If a friendship of yours has ended, decide now that the things you know stay where they are. Not in a story, not as a correction when somebody praises them. You will be glad of that in a few years, whichever way you feel about them by then.