A frustrated NICOLE RICHIE has called off her long-delayed wedding to rocker JOEL MADDEN – and NOW she’s telling pals the marriage may NEVER happen.

After announcing their engagement in February, the couple pushed back their nuptials numerous times – and now Nicole, 28, has pulled the plug on planning her big day, saying she won’t move forward unless they first fix their rocky relationship.

"Their wedding is off for now," disclosed an insider.

"Nicole is disgusted that Joel’s thrown himself totally into his work, and she’s now questioning his commitment to family life.

"It’s become a joke among Nicole’s family and friends how many times she’s planned and postponed the ceremony. Nicole’s dad Lionel even started referring to her as the little bride who cried wolf."

The sad reality is that Nicole and Joel, 31, have grown apart, according to the insider.

"Nicole is disturbed that Joel seems more interested in being on the road with his buddies, boozing and hanging out in bars with groupies than he is in sharing family time in L.A.," confided the insider.

"The fire is dying."

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