Not A Safety Net Nor An Idiot

What do you do when a secret is leaked to you and the information it holds makes you think that your friend is going to make the biggest mistake of his/her life?

Go up to you friend and confront him/her about it? Then how do you protect the relationship between you friend and the person with the loose-lips? I'm fine if my relationship with my friend is severed but I won't be the one to break other friendships just because I have an opinion. It's quite obvious that the relationship between you and your friend isn't very stable when she/he tries to hide something that they know you will feel strongly against. Then once she/he continues to go through with the plan, am I to give up on our friendship? The reason being that I won't be the same person to lend you my shoulder to cry on or the patient listening ear anymore. You know it's obviously a bad decision and yet you go through with it, then I won't just sit around waiting to be the safety net for you to fall into.

Don't tell me you treasure our friendship when you resort to such acts. Don't tell me things you don't mean as they will eventually backfire on you. Don't think that because I need glasses that I'm blind. Don't think because you whisper that I can't hear. Don't think because I nod at what you say that I'm naive enough to believe every word as the truth. Don't think because you've got buddies everywhere that you're the only one who has easy access to information.

Don't think I'm nice.
Don't think I'm stupid.
YOU SHOULD KNOW ME BETTER THAN THAT!