Jana Kramer Talks Strengthening Marriage After Husband Mike Caussin's Treatment for Sex Addiction

Jana Kramer and Mike Caussin Releasing Relationship Self-Help Book: 'We Have the Tools'

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Mike Caussin and Jana Kramer are getting candid about sex addiction, infidelity and strengthening their marriage.

On Tuesday, the couple — who tied the knot in 2015 and share two children together, daughter Jolie Rae, 4, and son Jace Joseph, 21 months — debuted their new book The Good Fight: Wanting to Leave, Choosing to Stay, and the Powerful Practice for Loving Faithfully.

In the relationship self-help book, Caussin, 33, opens up about struggling with sex addiction, as well as his history of infidelity. "I've dated only a few women in my life," the former NFL player writes. "Most of my relationships can be more described as 'talking to,' which essentially means we were sleeping together but I never committed enough to get my feelings involved. And when I did commit, I inevitably cheated. I couldn't be alone."

Rich Fury/Getty Jana Kramer and Mike Caussin in March 2019

The athlete also described how he was impacted by going from his fame in the sports world to becoming better known as his country singer wife's husband.

"I lost my sense of self and identity," writes Caussin. "A lot of professional athletes struggle with that transition when they retire from their athletic careers, but the added layer for me was being married to a celebrity with a certain amount of notoriety."

"Now, I loved and still love being Jana's husband, but early in the relationship I had no idea who I was anymore," he adds.

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Courtesy of HarperOne

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In an essay for Good Morning America, Kramer, 36, addresses Caussin's multiple affairs that "rocked our world" in 2016. After Caussin sought treatment, the pair reconciled and renewed their vows in 2017, and now she says rebuilding their relationship was "worth fighting for."

"The pain consumed my every thought and physically hurt me more than I thought I could handle," she writes in the essay of learning of her husband's cheating. "Thinking back, it seems like a terrible nightmare that I wouldn't wish on anyone."

"In a weird way though, I'm thankful for it because throughout the years of mending our relationship, I have had the chance to learn so much about myself, and who I am as a woman," continues Kramer. "It takes a lot of courage to leave, and at times I used to think that I was weak for staying."

"Truthfully, I didn't want to be without my daughter every day and I'm too stubborn to have Mike's mistakes dictate having to spend every other holiday with her," she says. "What I learned though, is that I wasn't weak. The decision to stay and fight for a man I didn't even know took a lot of guts and strength."

Kramer says she "grew in therapy, and in return I grew as a woman, I grew as a partner and because of the work my husband was doing on himself, we grew together."

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Back in May, Kramer spoke to PEOPLE about the process of writing The Good Fight, revealing that Caussin initially wasn't on board with divulging so many personal matters, even though the the Whine Down podcast co-hosts have previously been open about the issues.

"[At first] I was writing a book about my life and our relationship, and at the time we did a treatment that I gave to Mike. He just ripped it up and was like, 'You're not releasing this.' [He was] just full of shame, which I get [now]. At the time I was like, 'I want to help people,'" Kramer said.

"This was within the first calendar year of everything happening," added Caussin. "It was still real new for both of us. I was still so stuck in shame that I didn't see the silver lining of how we can help other people because I was so small at the time."

"We're not trying to claim that we have it all figured out. We learned from clinical professionals that we've had in our lives steer us in the right direction. We have the tools," said Caussin. "[The book] is vulnerable, it's authentic, it's direct, it's funny, it's passionate."