Brandon Blackstock was reportedly "extremely jealous" of Kelly Clarkson during their relationship.
The 39-year-old singer filed for divorce from ex Brandon, 44, after seven years of marriage in 2020 and an insider has claimed that the talent manager was envious of her success on both her eponymous talk show and 'The Voice'.
A source told Us Weekly magazine: "The relationship had been on the rocks for a long time.
"She was the high-income earner with a wildly successful talk show, and is the star of another hit show 'The Voice'. Brandon was extremely jealous of it and made her know it."
The insider added that Kelly is feeling "extremely confident" as she waits for the divorce to be finalised and is looking forward to celebrating her success without feeling "ashamed".
They added: "(Kelly) can finally enjoy her success without feeling ashamed. Kelly doesn't take credit for her success but shares it with the team she works with. It's just who she is."
The 'Since U Been Gone' hitmaker – who shares daughter River, seven, and son Remington, five, with her former partner – had reportedly become wary "that Brandon was just using her for money and lifestyle" before they separated.
The source said: "The marriage was really, really awful at the end... Kelly felt that she could no longer trust Brandon. She had a lot of questions that he just couldn't answer.
"She just wasn't willing to look the other way anymore."
Kelly recently won ownership of her Montana ranch property as she was awarded most of the pair's assets during a court hearing last week but Brandon will continue to live there as long as he pays the monthly fees to keep it running as he hopes to become a full-time rancher.
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