The pair reportedly had been dating since April.

"They had a great time together but they are just in different places in their lives right now," one insider told the celebrity weekly.

"He never ends things with a clean slate," one of Mayer's friends told People. "He likes to dwell on these relationships and sort everything out before saying goodbye for good."

The break-up was first reported Wednesday by Britain's Mirror newspaper, which said the couple decided earlier this week to stop dating after spending some time apart.

People said Aniston and Mayer's respective publicists had no comment for its story.

Aniston's representative last week dismissed as "complete fabrications" reports claiming the actress and the singer were set to wed.

OK! magazine reported Aniston was planning to marry Mayer this fall. The publication also offered details about what kind of dress the actress planned to wear and what her guests would eat and drink.

Meanwhile, Star magazine claimed Aniston, who was previously married to actor Brad Pitt, wants to have Mayer's baby as "Brad and Angie's twins wow the world."

Pitt's current partner, actress Angelina Jolie, gave birth to their fifth and sixth children last month.