Kate Gosselin is zonked.
In an interview taped on Wednesday -- when her ex Jon Gosselin sued for custody of their 8 kids, an exhausted-looking Gosselin admitted that balancing motherhood, Dancing with the Stars and lawsuits is "tough."
"It's very difficult," she tells E! News from an NYC dance studio as partner Tony Dovolani stands by. "I can't put my life aside and dance for six hours a day."
The 35-year-old mom adds: "It's not my lack of ability, but lack of presence. I struggle with this every day. But I have determination."
The reality mom -- whose new TLC show Twist of Kate was announced Thursday -- generally ignores the catty snipes from the judges. "I take the constructive criticism only. I have to feel good about the dance and myself."
What did her kids think of her poorly-received "Paparazzi" paso doble routine?
"They didn't understand the storyline, but they understand who the paparazzi are," she admitted. But the children don't even see her routine when it airs live. "The kids fall asleep before I get to dance," she says. "One child asked me, 'Can you please dance earlier?'" She adds that "they worry about what I look like. They say Tony looks good. They say I look beautiful."
Dovolani declares to the camera, "I strongly believe in her. The very first words she said on our show was, 'I want to win.' I told her today that I still see the possibility of her winning."
But multiple sources have told Us Weekly that, off camera, Dovolani has had it with his "argumentative" dance partner. "He can't wait to get rid of her, even if it means losing early," a source says in the new issue, out now.
"He doesn't want to be around her unless he has to," another show source insists.