INTRUDER ALERT

Hopefully, this is something that most people can relate to. Say you have a friend right, and that friend has a companion. Now, your friend isn't perfect (of course) but for the most part he/she does right by their companion. The companion on the other hand is a bit different. Despite being obligated to your friend, they do things behind your friends back and though they never verbally said so, expect you to keep your mouth closed. Because knowing your friend, even if you did tell them they wouldn't believe you and you would be risking a good friendship by intruding into their business.
My question is this....Do you STILL tell them and risk it or do you just let them find out the hard way???

--Songbyrd--