Jeff Vespa / WireImage 1 / 7
Jeff Vespa / WireImage 1 / 7

When they married in 1999, Courteney Cox and David Arquette engraved their wedding bands with the phrase, "A deal is a deal." But now the rings are off, and the terms of their deal have changed dramatically in recent months.

In a candid and at times emotional phone interview Tuesday morning with Howard Stern, Arquette, 39, discussed intimate details about their marital meltdown, including his rumored dalliance with a waitress and Courteney's alleged closeness with her "Cougar Town" co-star, Brian Van Holt.

RELATED VIDEO: The latest on their split

Let's start with the reports linking the actor to Jasmine Waltz, a drink-slinger who has reportedly been seen in the company of Ryan Seacrest, Chris Pine, Jesse McCartney and Paris Hilton's ex, Doug Reinhardt (last July, she denied punching Lindsay Lohan, famously sniping, "That disturbed little train wreck is delusional").

According to Arquette, who admitted to having a few drinks on Monday night to deal with the fallout of the breakup announcement, "I did have sex with her once ... maybe twice."

But he and Courteney, 46, were already separated at the time, he says, adding that he doesn't want people to get the wrong idea. He insists he was the picture of fidelity during their 11-year marriage, and that this was his one post-separation "conquest."

So, what caused the breakup?

David traces it back to their 11th wedding anniversary in June. Cox gave him a motorcycle and said, "I don't want to be your mother anymore." Translation: No more nagging -- do what you want.

When they left soon after to film "Scream 4" in Michigan, they hadn't had "sex in about a month or so," Arquette unwisely overshared, his voice occasionally wavering. "Since then, it's been four months or so. We're not having sex, and I completely understand. She's in a place of wanting to be real. She's an emotional being. She's an amazing woman. If it doesn't feel right -- she doesn't feel like bonding in that way."

David acknowledges that he cut loose during shooting, partying with the cast and getting another tattoo (a move that didn't thrill his missus).

When filming wrapped, Courteney "was very reflective of where our relationship was," he recalls. "After we got back, we decided to get into a trial separation."

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Arquette, who admits he can be a "moody" guy, says Cox told him he was free to see other people: "I want you to be able to do whatever you have to do."

When Stern points out that's a two-way street, the actor brushes off reports that surfaced last spring claiming Courteney was sneaking around with Van Holt.

"I do believe her," he declared. "I truly don't think she ever had an affair."

RELATED VIDEO: Watch "Cougar Town"

When asked if they were possibly having an emotional affair, Arquette was non-committal, but did note, "Part of the terms of our separation was that I was allowed to see other people, and so was she."

Cox, he sighed, has "her issues. She tries to take on everybody's problems. She's trying to be the mother to everyone. That's why she doesn't want to be the mother of me anymore."

Adds David, "I've been going to therapy. I'm trying to grow up. I'm trying to be true to myself. Trying to figure out myself and my world, as is she ... She wants me to be who I am. She needs to make that decision if this is person she wants to spend her life with or not."

As for their 6-year-old daughter, Coco, who was treated to breakfast with her dad after his Stern interview, they told her about their separation during a picnic at the beach.

She asked if they were getting a divorce. The answer: "No, we're taking time off to know ... what we want out of our mate better."

"I've been begging Courteney to get back with me," confessed David. "She's conflicted, too."

He said all he wants is for her to be happy, "more than I want happiness for myself."

"I love her with all my heart, and she loves me with all her heart," professed Arquette. "She's the greatest woman that ever lived."

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