Jennifer Aniston is apparently giving ample of relationship advice to Courteney Cox. Rumours suggest that the 51-year-old actress's relationship with Johnny McDaid was on the rocks.

Cox, who is best known for her role as Monica Geller on the NBC sitcom Friends, and the 39-year-old Snow Patrol guitarist reportedly split before Thanksgiving. TMZ reported that he moved out of both her homes in Malibu and Los Angeles, and flew back to England.

"Courteney and Johnny had been rowing for months - mainly over his constant stalling over their wedding," a source told Closer magazine. "Jen's telling Courteney to be patient and has drawn on her own experience with Justin (Theroux), after waiting three years to wed following their engagement."

"She knows how much Courteney loves Johnny and worries she's let the pressure of a wedding ruin what they have. She's urging her not to give up on him – even if they need therapy to work through some of their issues," the insider added.

"She's totally heartbroken and while she appreciates Jen's point, she isn't sure if their relationship is salvageable," the source continued.

In June 2014, Cox had confirmed her engagement to McDaid on Twitter. She posted a selfie of the two and wrote: "I'm engaged to him!"

Cox had previously revealed on The Ellen DeGeneres Show that her daughter Coco Arquette is looking forward to her nuptials. She said: "Coco is very excited about the wedding. I was going to hire a wedding planner, but apparently she wants to do it. She's 10, but she wants to do everything. She wants to be the maid of honor, which I think is weird. She wants to be the flower girl, all the bridesmaids. She's very excited about it."