Courteney Cox: David 'is my best friend'

Courteney Cox and David Arquette remain close and run their production company together, Coquette Productions.

STORY HIGHLIGHTS

• "[David Arquette is] my favorite person in the world," Courteney Cox told PEOPLE


• Cox and Arquette separated in fall 2010 after 11 years of marriage


• "[We went out to celebrate] David's one year of sobriety," Cox says

() -- They may be the happiest unmarried couple in L.A.

"He's my favorite person in the world," told PEOPLE of her estranged husband David Arquette at the "Cougar Town" TCA party. "He's my best friend. No matter what happens in our future, he's my very best friend."

Cox and Arquette, who after , remain close and together run their production company, Coquette Productions, that has some art-imitating-life projects in the works.

Cox tells PEOPLE, "We sold one show, 'Ten Year,' about a couple who separated after 10 years of marriage. It's not really about David and me, but it's something we related to and we thought we should tell a story about people who could actually get along after being separated. It's telling a different version."

As far as Arquette's recovery after rehab for alcohol abuse, his No. 1 supporter says they just celebrated a milestone. "[We went out to celebrate] David's one year of sobriety," Cox says. "He's great. Good for him."

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