Jen and Courteney's friendship on the rocks

Former Friends co-stars Jennifer Aniston and Courteney Cox have been close pals ever since their skyrocketing career on the '90s sitcom, however new reports suggest the pair's friendship is on the outs.

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A longtime mutual friend of the duo opened up and revealed: "Courteney has been pushing Jen to get pregnant for years! She's given Jen non-stop baby and pregnancy advice, and Jen is sick of it."

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The 45-year-old Horrible Bosses star has been seen paling around with comedian Chelsea Handler and has been reportedly considering making her one of her bridesmaids for her upcoming wedding to Justin Theroux.

Jen and Courtney back at an event in 2010. Source: WireImage

The source admitted: "She doesn't want a friend who's a total know it all. She'd much prefer to spend her time with someone like Chelsea, who would never tell her what she should or shouldn't do. Courteney can't stand Chelsea. Courteney thinks she loud and crass--while Jen think Courteney is taking things too seriously and is acting like a jealous teenager. It's gotten to the point where neither one of them wants to make the effort to keep the friendship going."

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The insider also revealed how the 49-year-old Cougar Town actress failed to invite Jen to her birthday party last year.

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She revealed: "That's how far apart they've gotten. It was beyond weird that Jen was left off the list because so many of their mutual friends were there, like Laura Dern, which just goes to show that these two are nothing like they were."

She concluded: "It's really sad but the friendship has basically evaporated."