'Welcome to Plathville' : Max Kallschmidt Admits to Micah Plath What He Did to Moriah: 'I F—ed Up'

After last week's episode of TLC's Welcome to Plathville, it was clear that whatever happened between Moriah Plath and her longtime boyfriend Max Kallschmidt wasn't pretty.

The young couple had been together for more than a year when they split towards the end of 2021. Max, 21, gave Moriah, 19, a promise ring during the show's third season, and planned to move to Tampa, Fla., with her.

But in the season 4 premiere, Moriah could barely leave her room, leaving her housemates — her brother, Ethan Plath, 23, and sister-in-law Olivia Plath, 23 — concerned. To lift her spirits, they surprised Moriah with a visit from her brother Micah Plath, 21, for Thanksgiving.

When Micah asked her what happened with Max, she simply broke down in tears.

In an exclusive clip from this week's episode of Welcome to Plathville, Micah confronts Max and asks him exactly what happened.

"I f—ed up, man, pretty bad," Max begins, immediately breaking down into tears. "I have this good buddy of mine that's a good bit older than you and I. We used to work together and we were kind of celebrating his retirement at his place and he invited his lady friend over that I knew he liked. And so I was trying to be his wingman. And so I took things a little too far. I was just flirting with her, and that led her to think that it was okay to try and kiss me, which she did."

Micah puts his face in his hands as Max continues: "I told Moriah, like, 'Oh, this happened,' and, like an idiot, I said, 'I'm proud of myself for not letting it go too far.' She broke up with me, which is reasonably so."

"The biggest emotion I felt while he was telling me what happened was anger," Micah says in an interview after the conversation. "Now it's not only betrayal on Moriah's part but also the friendship that we had. Most of us didn't think he was capable of that."

"I understand if you don't really want anything to do with me but I just ask that you be there for her," Max adds.

"Uh, yeah, I love Moriah. She's the sister I'm closest to and anytime she gets hurt, I get hurt too," Micah says. "And I will say I'm really f—ing disappointed in you."

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But Max isn't quite finished confessing his sins.

"After all of this, we kind of like just took a real hard reflection on our relationship, and we dived into the clothes that she wears, and then that just kind of made me pissed off and in my anger, we just erupted into a big argument," he tries to explain. "I definitely said some things that were hurtful."

Crying, Max concludes, "I want to do better."

In the season premiere, Moriah hinted that infidelity may have played a part in the end of her relationship.

"A couple weeks after I moved to Tampa, Max called me one night and just said he made a mistake," she said in a confessional interview. "I'm not going to go into details. Since then, I have been in a dark place."

Later, she added: "I'm scared to share what happened with anybody because if I say it out loud, it becomes real."

Welcome to Plathville airs Tuesdays at 10 p.m. ET on TLC.