Kristen Stewart is never going to be totally comfortable with the fame game.

In an interview conducted before her July 17 cheating scandal, the Twilight star, 22, opens up to British Vogue about her image -- and admits she understands why people criticize her for seeming aloof, detached, and unimpressed with celebrity.

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"I know if you haven't thought about how you want to present a very packaged idea of yourself, then it can seem like you lack ambition," the On the Road actress explains. "But, dude, honestly? I can't. People expect it to be so easy because there you are, out there, doing the thing that you want and making lots of money out of it."

But confidence doesn't come that easy, she insists. "I'm not that smooth. I can get clumsy around certain people. Like if I were to sit down and think, 'OK, I'm really famous, how am I going to conduct myself in public?' I wouldn't know who that person would be!"

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Ready or not, Stewart -- who was caught cheating on boyfriend Robert Pattinson with her married Snow White and the Huntsman director, Rupert Sanders, in mid-July -- will have to face the spotlight's glare once more as she makes her first red carpet appearance Thursday at the Toronto International Film Festival to promote On the Road.

The actress has been keeping a low profile in the wake of the scandal, splitting her time between a friend's home and her parents' Los Feliz pad.

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"She isn't sleeping and she stays up all night crying," a source recently told Us Weekly of Stewart, who is desperate to get back together with Pattinson, 26. "She's close to a total meltdown."

This article originally appeared on Kristen Stewart: "I Can Get Clumsy Around Certain People"