Chris Isaak Comes to LeAnn Rimes’ Defense

Despite her scandalous personal life, Chris Isaak can't stop singing the praises of LeAnn Rimes. "I've known her always to be nothing but sweet," says Isaak, who performed with Rimes at the MTV Movie Awards June 1.

"She's always so friendly and so nice and is someone who backs you up, onstage and off."

Check out red carpet photos from Sunday's show.

Rimes made headlines in March after Us Weekly revealed that she had been having an affair with her Lifetime TV movie costar Eddie Cibrian. (While never denying the tryst, Rimes admitted she and husband Dean Sheremet were going through a "difficult time.")

See photos of LeAnn and other stars caught cheating.

The drama heightened this week when Cibrian's wife, Brandi Glanville, deemed Rimes "a stalker," alleging in the new issue of Us Weekly that Rimes is constantly "texting and calling" her husband. "She never let on that there was any problem in her life," says Isaak when asked about Rimes' personal life. He says she was "in a good mood" as they performed a medley of raunchy songs (penned by host Andy Samberg) with actor Forest Whitaker.

See photos of more celebs acting silly.

Adds Isaak, "We were all excited and a little scared. She's a great singer and a nice lady. It was fun working with her."

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