The celebrity news website said Aguilera, 29, and Jordan Bratman split up a few months ago, but have not yet decided whether the divorce.
"They are now living apart, and they will see how that goes," Us Weekly quoted a source close to the "Beautiful" singer as saying.
"They were very much in love. But over the last six months, it became clear they were more like friends than husband and wife," the unidentified source said.
A spokeswoman for Aguilera said she had no comment at this time.
Aguilera, who had a huge early hit with "Genie in a Bottle", and Bratman, 33, married in November 2005 and have a two year-old son, Max. They met in 2002 while Jordan was working for Aguilera's music management company.
Aguilera, a former Disney teen performer, is due to star in her first feature film -- the upcoming musical movie "Burlesque".
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