Twilight co-stars Robert Pattinson and Kristen Stewart are a couple in real life

Maybe that was the reason Kristen Stewart always looked so moody at Twilight premieres?

The actress, 22, says she's given up the fags - but claims she wasn't addicted anyway.

'I wasn't addicted to nicotine. I just liked putting something in my mouth,' she declared on the  Conan O'Brien show  

We don't know if that's a good thing or a bad thing for R-Pattz.

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