Breaking Celebrity News can exclusively reveal that Jennifer Aniston is wading into best friend Courteney Cox's romance with Johnny McDaid, acting as a de facto therapist for the troubled pair.

"This wedding's been on and off more times than a light bulb, and Jen's genuinely worried Courteney's throwing the best thing of her life away by being difficult," an insider explained.

Aniston, 48, "is encouraging them to get pre-marriage counseling but acting as a sympathetic ear in the meantime, helping with ideas for spontaneous date nights and recommending tricks that helped her and Justin through troubled times," explained the insider.

As Breaking Celebrity News reported, Cox, 53, and McDaid, 41, have been going back and forth on tying the knot for quite some time, disagreeing on everything from where they should hold the ceremony to where they should set up a home together.

Said the insider, "Courteney's grateful, but it will take more than Jen's advice to get her and Johnny down the aisle!"

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