Kelly Clarkson’s nasty divorce with her ex rages on, but she vows to not let it destroy her.

Kelly Clarkson is opening up more about her “horrible” divorce from Brandon Blackstock, admitting co-parenting their daughter River, 6, and son Remington, 4, has been “tough.” Her confession comes on the heels of the news that Brandon, 44, is requesting $436,000 a month in child and spousal support (a total that tops more than $5 million a year) and that Brandon’s father, Narvel Blackstock, who owns Starstruck Management Group, has filed a claim against Kelly alleging she owes them $1.4 million in unpaid commissions. “The situation with the kids, the money...this divorce keeps getting nastier and nastier,” a source tells In Touch. But Kelly, 38, “is staying strong. No matter how ugly it gets, she’s vowed to not let this divorce destroy her.” Still, the there have been times Kelly felt she reached the breaking point, adds the source. “She’s juggling the kids while working on The Voice and her talk show, and all of it is wiping her out. The days are long, and most nights she comes home and just collapses into bed. But if you know Kelly, you know that she’ll work even harder when she’s pushed. So

Brandon can continue to throw wrenches into their divorce, but Kelly will keep fighting with everything she has in her.”