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Oh, snap! Jon Gosselin and girlfriend Liz Jannetta got into a major fight on the Thursday episode of VH1's "Couple's Therapy" -- so big, that it moved the father-of-eight to compare his current flame to ex-wife Kate Gosselin.

(Warning: this next part gets a bit graphic.) Leading up to the lovers' feud, Gosselin is taped in his room -- under his covers as he moans -- right when Jannetta walks in. Presuming the 36-year-old was masturbating, she immediately reacts and quips, "Ew."

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The petite blonde then drops F-bombs as she rails against her boyfriend: "It's humiliating," she says as Gosselin attempts to explain himself. "You are such a jerk. I'm like, ready to throw up actually," she says as she storms out of the room.

In his confessional, Gosselin explains, "I'm in the bedroom, I'm laying down. I'm just laying there, scratching myself and Liz thinks I'm masturbating," he says with an incredulous expression on his face.

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The couple tries to clear the air following the incident, but it only makes matters worse: Jannetta laughs when Gosselin tries to explain what had happened earlier in the bedroom. "I wasn't doing anything, I swear to God. Hands were down because I was scratching my balls," he said to his girlfriend, who burst out into laughter as she shook her head.

"Please don't play the victim role all the time," she retorted before walking away.

"I was disappointed that she didn't believe me, so then I got hurt," Gosselin recalled of their awkward talk. "So then I clam up and I drew my hood down. And I kind of just wanted her to go away."

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The TLC alum then likened his gal pal to his famous ex-wife: "When Liz laughs at me and walks away, it's like Kate," he confessed. "That's exactly how I feel."

(Jon and Kate, who divorced bitterly in 2009, also share eight kids -- twin daughters Cara and Madelyn, 13, and sextuplets Alexis, Hannah, Aaden, Collin, Leah, and Joel, 9. Following his eldest daughters' cringeworthy Today show appearance last Thursday, Gosselin called up TMZ hours later to address what the awkward interview: "I felt upset. I was laying there with Liz and we were like, 'Say something girls. Come on! Just say something. Anything.' And they didn't say anything and we were like, 'Ugh, this is horrible,'" he said of watching the segment with Jannetta.)


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