How to deal with backstabbers

In the article Set up ground rules to deal with backstabbers, Bill Repp explains that healthy people have enough confidence in themselves to go directly to a person who disagrees with them and try to clarify or resolve the issue politely. Backstabbers can't do that because they are often deeply insecure and lack confidence. Though they may appear to be supportive, they often withhold information you may need.

So how do you deal with them? Bill advises that in a nonthreatening manner ask: "I'd like us to agree that any reaction we have to each other's ideas or actions will be discussed personally with each other before they're discussed with anyone else. Could we agree to that?"

If the person claims ignorance on why you're asking this, say: "I'm concerned that other people may have been included in discussions other than the two of us. I'd like to think that you and I can handle situations involving us. In the future, when there are things you don't agree with completely, here's how I'd appreciate your bringing them to my attention..." In other words, never accuse, but continue to restate your need.