Jana Kramer & Mike Caussin on Auditioning for 'RHOBH,' and Fighting Through the Tough Times

Country star Jana Kramer and her husband, retired football pro Mike Caussin, have been living their lives like an open book. Always candid about the struggles in their marriage on social media and on their popular "Whine Down" podcast, they are now revealing even more via their book "The Good Fight: Wanting to Leave, Choosing to Stay, and the Powerful Practice for Loving Faithfully."

Jana and Mike spoke with "Extra's" Jenn Lahmers all about their book, breaking news about auditioning to join the "Real Housewives" franchise. Jana said, "I mean, we actually did [audition], but we never heard anything back. It was one of those [things] where we got the call [to audition] and, 'We're in quarantine right now, let's give it a try,' but nope — I couldn't handle it... I would come home every night and be like, 'They're so mean.'"

Jana, 36, explained the reason she and Mike, 33, are always painfully honest is, "I feel like we didn't really have a choice because he got outed when he was in sex addiction rehab, but from there I was like, 'Let's change the narrative. Let's help people...' I want the story how we were able to fight for each other... Marriages can go through the hardest of times, but you can make it through if you're willing to work."

Mike's infidelity was tabloid fodder in 2016, when his serial cheating led to rehab, but the two worked to save their marriage, even after his move to file for divorce while Jana was on "Dancing with the Stars." That doesn't mean it wasn't a rocky road "I was pissed when I found that out," Jana said of the divorce papers, "because I was supposed to be the one that filed for divorce. I think the entire CBS studios heard my, like, 'What?!' I was so upset."

They had some hard talks. "I was like, 'Why would you do that?' and he was like, 'Well, you won't let me see our daughter...' And that was wrong of me, totally wrong of me." She went on, "That was honestly what was the key factor in wanting to try, because him doing that, I was like, 'Maybe I do want to try.'"

Further sharing why she chose work through the marriage, Jana said, "I had six-month-old baby. I couldn't let his bad actions break our family apart, and knowing he was willing to fight for our marriage, I was like, 'Okay, then I'm in it. I'm gonna try, too.'"

Mike added, "If Jolie and Jana were gone that day, I probably never would have gone to rehab and I'd still be living an unhealthy lifestyle... Jolie was really the blessing for all of this to snowball into what it is."

In "The Good Fight," Jana and Mike reveal more tough moments and how they faced them together. Mike said, "The main objective is to allow people to look at their relationship in a different way, that fighting doesn't have to separate you all — it can bring you closer together." He urged couples to see fighting as "an opportunity to learn something more about the one you're with."

Jana chimed in, "It's just kinda normalizing fighting, too. Hey, you're gonna fight with your partner, and this is how you can have a healthy fight."