Kate Gosselin is no stranger to meltdowns and tantrums -- but on Sunday's episode of Sarah Palin's Alaska on TLC, the reality mom lost it as she's never lost it before.

"I'm miserable," Gosselin, 35, whines from a rainy campsite. "It kills me that people willingly do this [go camping]," she says. "Why would you pretend to be homeless? I just don't get the concept."

Indeed, a source recently told Us Weekly that Gosselin and Sarah Palin, 46, had "zero chemistry," and that Gosselin said that the trip was "the worst" of her life.

As her diatribe continues, the mom of 8 gets more and more hysterical. "I don't see hand-cleansing materials!" she shrieks. "This is not ideal conditions!"

Watch Gosselin's unforgettable freakout now.