"That did shock me," Bowersox told New York and New Jersey's Steppin' Out entertainment magazine, Star magazine reported Tuesday.
"I woke up Tuesday morning and he just had an epiphany. He wanted a simple, quiet life and I respect that. I'm glad he told me instead of sticking it out and realizing it later that he would be unhappy."
At the time, she described it as a "mutual thing."
The 24-year-old from Toledo, OH recently signed with 19 Recordings/Jive Records and told Steppin' Out that despite the shocking nature of her split from Kusian, she's ready to move on and focus on her music.
"We always had a real open and honest relationship with each other," she said.
"I've had to deal with a lot worse in my life. It was bad timing, definitely. But I feel like I've never been stronger in my life. It was nothing that I couldn't handle. I just channeled all of that emotion into my performances."