Lady Gaga has defended Kristen Stewart's cheating.

The 22-year-old actress has publicly apologized to her boyfriend of four years Robert Pattinson after she was caught in a steamy make-out session with her Snow White And The Huntsman director Rupert Sanders, and Lady Gaga has weighed in, telling people to leave them alone.

"Geez this kirstew rob stuff is brutal. Makes me sad the way press acts. Hope they're ok (sic)," she wrote on Twitter.

Sources close to the actress insist she wasn't having an affair with Rupert and it was a fleeting mistake. "Kristen is absolutely devastated. It was a mistake and a complete lapse in judgment," an insider said.

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