Jana Kramer shares two children with Mike Caussin, whom she filed for divorced from last month

Jana Kramer is focusing on the good in her life amid her divorce from estranged husband Mike Caussin 

On Saturday, the country singer, 37, opened up about feeling "grateful" for her son Jace Joseph, 2, and daughter Jolie Rae, 5, both of whom she shares with Caussin, 34. Along with a snapshot of herself sitting with her kids outside, the mom of two detailed the happy moment on Instagram.

"Sunshine is good for everyone," Kramer wrote. "I gotta be honest 2 weeks ago the sun was the last thing I wanted to see...but through grieving you start to see the light...even if it's a dim light it's still something I'm gonna be grateful for. "

The One Tree Hill alum added, "But I'll forever be grateful for these 2 and the forever light they add to my life."

Kramer received support in the comments section of her post in the form of heartfelt messages from many famous followers, including Carrie Ann Inaba, Deanna Stagliano, Sasha Farber and Faith Ford.

Jana Kramer
Jana Kramer with her children
| Credit: Jana Kramer/Instagram

Kramer first announced her split with Caussin on April 21 in an emotional Instagram post, writing, "'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."

The actress added, "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.  It's time to heal."

In Kramer's Williamson County, Tennessee, divorce filing, recently obtained by PEOPLE, she cited "inappropriate marital conduct, irreconcilable differences and adultery" as grounds for divorce from Caussin.

The filing also revealed that the pair officially separated on April 20, just a day before PEOPLE learned that Kramer decided to file for divorce due to infidelity.

Caussin has not responded to PEOPLE's request for comment in regards to his estranged wife's allegations.

Mike Caussin and Jana Kramer
Mike Caussin and Jana Kramer
| Credit: Todd Williamson/E! Entertainment/NBCU/Getty

In the filing, Kramer requested that the court uphold a postnuptial agreement the pair had made after getting married and that she has primary custody of her kids, with allowed visitation times with Caussin. She also asked that Caussin cover her legal fees.

Infidelity has been an issue the couple has opened up about in the past. They previously separated in 2016 due to similar issues and documented some of their past marital problems in their book, The Good FightWanting to Leave, Choosing to Stay, and the Powerful Practice for Loving Faithfully.

According to the pair, Caussin filed for divorce in 2016 when Kramer was on Dancing with the Stars and he was seeking treatment for sex addiction. (They ultimately decided not to get divorced at the time and went on to renew their wedding vows in December 2017.)

"Mike was in rehab and I was in an all-out war with my emotions. Most days, I would push Mike out of my brain and tried to live in the world as if he didn't exist," Kramer wrote in a passage that she later read on their Whine Down podcast. "Other days I was too weak to push and I missed him, and I hoped he would be in the audience watching me perform, rooting for me."

Kramer added, "The only times that gave me calm was when I looked at our baby girl. I knew that regardless of the outcome, I wanted the best for her."