Jen Aniston bans John Mayer from shacking up until he agrees to set wedding date, sources say.

"Jen is holding John’s feet to the fire," a friend of the actress told The ENQUIRER.

"She made it clear to him over the holidays that it’s all or nothing when it comes to their relationship. Deep down, Jen worries that with John it’s ‘once a player, always a player.’

"This is her way of breaking him of his womanizing ways."

After a whirlwind love-fest that began in April 2008, 31-year-old John proposed to Jen – who turns 40 on Feb. 11 – last June. The couple split up in August, only to rekindle their romance in mid-October.

As The ENQUIRER exclusively reported in December, Jen revealed to pals that their wedding was back on, with a star-studded ceremony set for later this year.

But while John’s said "yes" to a wedding, "he’s dragging his feet on setting a date," explained the friend.

"Jen is frustrated. She doesn’t see any other way to get that ring on her finger."

Jen – who’s worth well over $100 million – divides her time between a small Hollywood Hills home and a newly remodeled $15 million Beverly Hills mansion. John, meanwhile, has a home in Pacific Palisades and an apartment in New York City.

"Jen rarely lets John sleep over at her Hollywood Hills home, and she NEVER allows him to spend the night at her new mansion," divulged the friend.

"Jen hopes the barrier will irritate John and push him to get the ball rolling on their wedding.

"John is so frustrated that he’s offered to let Jen move into his home. But Jen is sticking to her guns," the source divulged.

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