Katy Perry Unfollows Russell Brand on Twitter

Katy Perry is cutting Russell Brand out of her life in more ways than one.

The 27-year-old "Firework" singer has unfollowed her soon-to-be ex-husband on Twitter. As of Friday, Perry is still one of the 78 people Brand subscribes to via the social networking site.

PHOTOS: Katy's crazy cleavage

It's not surprising, given that Perry is only communicating with Brand, 36, via phone or email. "She's limiting those interactions," a source tells the new issue of Us Weekly (out now). "He's being so atrocious that she feels like she never really knew him."

VIDEO: Why did Katy and Russell call it quits?

Perry has been keeping Brand off her mind by focusing on her career: she performed in Jakarta, Indonesia, on Thursday, and she recently shot an Adidas ad in Santa Barbara, Calif.

"She doesn't want to look battered and have people for sorry for her," a Perry source tells Us. "She's very strong and confident."

PHOTOS: Katy and Russell's zany romance

For much more on the couple's nasty split -- including Brand's plans for a tell-all book documenting his 14-month marriage to Perry -- pick up the new issue of Us Weekly, out now!

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