Jennifer Lopez is no longer the easygoing Jenny from the Block!
RadarOnline.com can exclusively reveal Lopez "was a complete diva" and "very difficult" while attending this year's Grammy Awards in L.A.
"Jennifer wouldn't allow anyone to tell her what to do," said a source.
"During rehearsals, she was barking at the dancers and she kept breaking down and getting frustrated because it wasn't going her way," continued the source.
And shortly before the show kicked off, "she demanded preferential treatment over everyone, including Lady Gaga," said the source, who noted Lopez posed with the "Shallow" singer on the red carpet, but it was all for publicity and "not because of their love for one another."
"She definitely lived up to her reputation as difficult," said the source.
Lopez was slammed by Grammy viewers for her participation in the Motown tribute, but fellow singer Smokey Robinson came to her defense.
"I think anyone who is upset is stupid," he said.
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