The Whistle Blower

This isn't the FG Whistle blower policy,this is a socially induced whistling blowing fever..... What would you do if you saw something you shouldn't have seen as concerns............ Let me rephrase -If you caught your friend's husband OR wife cheating,would you tell? what would be your reason for doing so?..If your friend told you that your wife OR husband was cheating with proof,how via IFTTT