Jana Kramer Confirms Why She Filed for Divorce from Mike Caussin

Days after Jana Kramer announced her split from Mike Caussin, she has confirmed the cause of their breakup.

In the divorce filing obtained by "Extra," Kramer listed the reason behind the separation as “inappropriate marital conduct, irreconcilable differences and adultery."

The docs also reveal that the pair had a postnuptial agreement.

Along with requesting joint  legal and physical custody of their two children — Jolie Rae, 5, and Jace Joseph, 2 — Jana is asking for Mike to pay alimony and her legal fees.

Last week, Kramer announced their split on Instagram. She wrote, “‘It's time.' As I try to make sense of a reality I never wanted to believe could be possible again, those words have now become a reality. I've fought y'all. I've loved hard. I've forgiven. I've put the work in. I've given everything I have, and now I have nothing else to give."

“Please know that I still believe wholeheartedly in marriage, love, and rebuilding. I just can't fight any longer,” Jana stressed. “It's time to heal. Thank you for all the love, heart, and support, in many ways you have fought on this journey alongside me, and for that I am grateful. I'll always encourage you to continue the good fight, but you can't fight it alone. 💔."

"Extra's" Billy Bush was able to get ahold of an emotional Jana, who said she was sad and embarrassed that the marriage had failed.

Sources close to Jana told Billy that infidelity was what led to the split. Mike’s alleged trysts escalated over the last year and there was a recent straw that broke the camel’s back.

Caussin has yet to comment on their breakup.

Just months ago, the pair opened up about the tough times while promoting their book "The Good Fight: Wanting to Leave, Choosing to Stay, and the Powerful Practice for Loving Faithfully."

Jana explained the reason she and Mike were always painfully honest, telling “Extra’s” Jenn Lahmers, "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."