Name: The Underminer

Identifying Characteristics: She puts you down in subtle, almost imperceptible ways and makes tiny digs that keep you up at night, wondering just what she meant when she said, "You're SO BRAVE to wear that dress" or "I could never eat a whole burrito -- like you!" You wonder, was I just insulted? Am I crazy? Did anybody else hear that bitchy little comment? Gah!

Field Study: "Alison once told me she really loved the 'little Web site' I worked for but asked, 'Didn't it get tiresome writing about such silly things?'" says Jenny, 30, from Los Angeles. "Keep in mind -- Alison writes glorified celebrity profiles for a living. I wanted to throttle her from through the computer."

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Why You Keep the Underminer Around: Perhaps it's amusing to listen to her snark out others, but eventually the Underminer will turn her nastiness on you. Like your mama probably told you, some people have to put others down to make themselves feel good. Look up "masochism" in the dictionary and learn to let this friend go.

Got a Friend Terrorist -- a super-toxic friend -- you want to tell us about? Share your story in the comments or drop us a line! We promise we'll change all identifying characteristics and incriminating details.

For a great example of the Underminer at work, check out this short clip from Mike Albo: