One of my favorite phrases from Tanach is “Diracheha Darchei Noam”. I believe that this phrase gives us an idea of how G-d wants us to act, and how to emulate Him. This would very much apply to how one should rebuke someone for a wrongdoing. It should be done in a non-threatening, pleasant, and soft-spoken way. Not by throwing rocks. Not by saying how “hurtful it must be for your relatives.”
I believe this phrase tells us that G-d wants us to do everything in a positive way. Even rebuking someone, which can be viewed as a negative experience, should be done in the most pleasant way possible. And definitely not through telling someone else about it, which (as others have pointed out) is almost certainly lashon harah, and can only end up negatively.