EXCLUSIVE: 'Duck Dynasty' Wife Jessica Robertson Talks Eating Disorder and First Marriage to Her Youth Ministe

Now is the time for Jessica Robertson.

The Duck Dynasty star talked to ET about the book she and her husband, Jep Robertson, wrote together -- The Good, the Bad, and the Grace of God: What Honesty and Pain Taught Us About Faith, Family, and Forgiveness -where openly talks about her first marriage to with her youth pastor, at age 18. This is something she even kept from her children at first.

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"The kids actually did not know that I was married before -- and it's something that we were going to share later on when they were a little more mature," she exclusively tells ET. "But I really felt like this was an opportunity to share with the world some of the struggles that I went through with that, and coming out through the grace of God. You know, coming out the other side, and meeting Jep, and turning my life around."

Jep and Jessica now have four children together: Lily, 11, Merritt, 10, Priscilla, 8, and River, 7.

"We've been married for 14 years now. So that's not who I am anymore," she continued. "It's not that we were hiding it, it just wasn't a topic of discussion with our kids."

In the book, Jessica shares how her first marriage came to be, writing that she was initially "unsure and scared" when her youth pastor expressed his feelings for her when she was just in high school, between her junior and senior year.

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"I also started to feel that I should be in love with him even though I wasn't in love with him," she writes. "Everyone said I was the luckiest girl in the world to have snagged him.”

Jessica, now 34, tells ET that she attributes many of her problems during her first marriage to being young and sheltered.

"I was really naive at the time and I was a people pleaser," she admits. "If I could have just made a few other decisions when I was younger, I wouldn't have made so many mistakes."

The reality star also opens up about her past struggles with an eating disorder around the time she met her first husband.

"I think a lot of girls struggle with that," she says. "I wouldn't eat anything with fat in it. I would go as far as getting powdered skim milk because it had fat in it."

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In the book, Jessica tells a more dire story.

"I started drastically cutting back on calories and working out harder and harder," she writes. "I used a calculator to track the calories I ate and sometimes made a meal out of just a few marshmallows or a bowl of low calorie cereal.”

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The path back to religion amid her struggles and after her initial divorce – she ended the marriage after one year-- Jessica admits, was a bumpy one.

"Not that I was depressed all the time but I just was unhappy," she tells ET. "And so leaving the marriage was my choice -- the blame was totally on me but yeah after that I just felt kind of hopeless," she said.

"I reached out to the friends I went to high school with and they were heavily into the college scene and partying and drinking and sleeping around," she continues. "So I started hanging out with them and I fell right into that lifestyle too."

"I fell flat on my face before searching for Jesus."

Eventually, Jep writes this gave her a reputation as a "girl of ill repute," and a church elder warned him to stay away from her. "He began throwing Bible verse after Bible verse at me about adulterous women, divorce, and remarriage…Then he began to pressure me to end the relationship with her."

However, Jep says he understood Jessica's plight.

"I knew what had happened to Jessica with the youth pastor wasn't right," he writes. "She'd been taken advantage of, and while she'd gone into a tailspin and made some bad choices, she had given her life to Jesus, and He had given her a brand-new start."

14 years later and the couple is still going strong, so something's working right!

The couple’s book, The Good, the Bad, and the Grace of God, will be available June 23. Meanwhile, A&E announced Monday that Duck Dynasty will return this month, with a one-hour special about the show’s Las Vegas musical special airing June 17 and the new season kicking off June 24.