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When a rep for actress Abbie Cornish told in February that she had broken up with Ryan Phillippe, at least one person was surprised: Ryan Phillippe.

"I have a new rule: not to date anyone who has a publicist," Phillippe quipped during a Monday radio interview on Howard Stern's Sirius XM radio sho.

The actor explained that he and Cornish had privately ended their four-year romance face-to-face -- but no one had warned him of an impending public statement claiming Cornish had dumped him.

"Who announces a breakup? I don't understand that! There's no need for that."

Phillippe added, "I've been dumped on in the press for relationship stuff since Reese [Witherspoon] and I divorced." Phillippe and Cornish began dating in 2006 -- the same year he and Witherspoon split after seven years of marriage.

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"I'm tired of getting s*** on," Phillippe, 35, told Stern. "I don't feel like I deserve it. Things happen! How many people have you broken up with over your life?"

The actor and Witherspoon now share joint custody of their daughter Ava, 10, and son Deacon, 6 -- and, he said, "it's gotten to a place where we're great friends and great co-parents." Such great friends, in fact, that they console each other after breakups.

"After I had my breakup, she called, and after she did, I called." Witherspoon, 34, called it quits with Jake Gyllenhaal in early December after nearly three years together.

Phillippe didn't have much to say about Witherspoon's new beau, Jim Toth. "I trust her to make the right decisions around our children," he said simply "I hope she feels the same way."

He points out that his kids don't get too invested in their parents' dating lives. "If the kids care about mom dad, and if that's consistent and they feel protected that way, they don't they don't really care so much about who the parent is dating. They just don't."

To Howard Stern's chagrin, Phillippe also reveals that he and his ex-wife have not had "ex sex." "That hasn't happened," he told the shock jock.

Since the Cornish split, he said he's "enjoying the single-ish" life, although he calls himself a "serial monogamist..Either a girl is worth spending all of my time with or none of my time." He shoots down rumors that he's hooked up with Victoria's Secret model Selita Ebanks, Lindsay Lohan or Jessica Simpson. "I've never met Jessica Simpson!"