Hell hath no fury like Kelly Clarkson scorned! The original 'American Idol' just married Brandon Blackstock in October and seems blissfully happy -- so she didn't take lightly when rumors hit the 'net of Blackstock creeping around with lessers.

The whispers began after two women came forward on dirtbag website The Dirty, claiming to have maintained affairs with Blackstock. "We haven't slept together," one anonymous class act claimed, "but we've been intimate in other ways. I really hope his wife keeps her eye on him because he's not the great man she thinks he is." (Apparently this woman forgot that knowingly taking part in infidelity doesn't speak too well of her own character, either.)

Meanwhile, a few months ago, a Blackstock family friend accused the music manager of cheating on his ex wife, Melissa Ashworth, multiple times.

However, Ashworth herself denies the claims.

“This is ridiculous … this silliness,” Ashworth scoffed to Radar Online. “I have my two children [by Brandon] right here, who I love. I adore Kelly and Brandon as a couple, so if I say anything it’s going to be positive.”

Clarkson, meanwhile, hasn't been so cheery. The 'Underneath the Tree' singer, who's been battling brutal morning sickness, isn't amused by the rumors, and took to Twitter to shut her haters up.