Sources: Jennifer Aniston & John Mayer Split

By David Caplan

08/13/2008 at 12:55 PM EDT

Jennifer Aniston and John Mayer have called it quits, multiple sources confirm to PEOPLE.

"They had a great time together but they are just in different places in their lives right now," says a source of Aniston, 39, and Mayer, 30, who kicked off their courtship in April.

A friend of Mayer adds that a reconciliation isn't necessarily out of the question: "He never ends things with a clean slate. He likes to dwell on these relationships and sort everything out before saying goodbye for good."

The split was first reported Wednesday by the U.K.'s Mirror, which said the couple split earlier this week, after initially deciding to spend some time apart.

Reps for Aniston and Mayer have declined to comment.

• Reporting by K.C. BAKER and ALYSSA SHELASKY

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