Blast from the past. Jessica Simpson claims that she and Jackass star Johnny Knoxville sent “love letters” to each other while she was still married to her ex-husband, Nick Lachey. The singer opens up about how they grew closer in her highly anticipated new memoir, Open Book, which is set to be released on February 4.

Simpson, 39, says that she formed a connection with her former costar, 48, on the set of Dukes of Hazzard. “It was like Johnny and I were prison pen pals, two people who wanted so much to be with each other but were kept apart,” she writes in her new book obtained by RadarOnline.com. At the time, he was also with his now-ex Melanie.

As fans may recall, romance rumors were swirling around the dynamic duo when the film was released back in 2005. The “Irresistible” songstress was also going through a rough patch with her beau, now 46, so she turned for comfort elsewhere. “There was something Nick wanted from me that I no longer had,” Simpson explains. “An emptiness I couldn’t fill.”

Jessica Simpson and Johnny Knoxville
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The actress also opens up about “wanting so bad to be with” Knoxville, especially because they had established a stronger emotional bond. Simpson claims they never actually hooked up, but she did have feelings for him.

“It’s funny, I know, because I placed such an emphasis on sex by not having it before marriage. After I actually had sex, I understood that the emotional part was what mattered. And Johnny and I had that, which seemed far more of a betrayal to my marriage than sex,” she notes in the book.

The blonde beauty says it became especially difficult for her to feel confident about her relationship with the 98 Degrees star when they were filming the reality show Newlyweds: Nick and Jessica — which showed viewers what their life was like behind closed doors.

“We were not one of those couples that screamed at each other, let whatever fly out of our mouths, and then make mad, passionate love,” she writes. “No, we would yell at each other, and then he would go out of town and not answer his phone. Vegas or Miami with his boys. Or he would just stay out late to teach me a lesson.”

Jessica Simpson Out and About
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Simpson and Lachey ultimately parted ways and finalized their divorce in June 2006. She has since found love with her husband, Eric Johnson, and they share three children, Maxwell, 7, Ace, 6, and Birdie, 10 months. Lachey also moved on with Vanessa Lachey (née Minnillo) and they share three kids of their own.

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