2. The one who ONLY drinks with you

It doesn't matter what day of the week it is, she's the girl friend who somehow concocts a reason to drink. Thirsty Tuesdays? But the thing is, that is all you two do together. It's never just 'one drink,' either. Going to happy hour is just an excuse for her to drink infinitely, and then she just becomes her alter ego - blackout barbie.  You've told her "I'm not drinking for a while because XYZ legitimate excuse," and she just snaps at you or laughs at you because she truly believes that no one can exist in the city without drinking excessively. Is she really worth the hangover?

[Photo via @rachelzoe]

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