Kelly Clarkson admitted in September that divorce “is the worst thing ever for everyone involved.” But now her divorce from Brandon Blackstock has turned into an even bigger nightmare. On July 27, court documents emerged revealing that after attorneys for Kelly, 39, and her ex, 44, submitted arguments concerning the former couple’s property and children, River Rose, 7, and Remington, 5, an LA County court judge ordered the singer and talk show host to pay Brandon nearly $200,000 a month, effective as of last April. That’s $150,000 in spousal support and $45,601 for child support, even though Kelly has primary custody — plus an extra $1.25 million for Brandon’s legal fees. “She’s furious,” a source tells In Touch. “Kelly thought she knew her husband and their future, but it turns…