Matt and Brittany are not done throwing accusations at each other on I Love a Mama's Boy.
In an exclusive sneak peek at Sunday's episode of the TLC reality show, the titular "Mama's Boy" insists he has nothing to hide even as his ex-girlfriend Brittany is convinced he cheated during their relationship.
Brittany invites Matt to a park, supposedly to clear the air after she invited her coworker Vicky to lunch to "interrogate" him about his alleged infidelity.
In a confessional interview, Brittany explains what already went down. "I asked Matt the day we had lunch with Vicky if he was seeing someone else. He said no. He immediately blocked me on [social media] that day, and the next day a coworker tells me that he was out with a girlfriend, getting wine. That wasn't me! So … I feel like I'm going to start shaking."
The exes' meetup in the park immediately turns tense as Matt arrives with his hands in his pockets and Brittany gives him the cold shoulder.
"I didn't want him to look at me, I didn't want him to touch me — he said I looked nice or something — don't tell me I look nice," Brittany says in a confessional. "Don't try to hug me. Don't even look at me for too long. He doesn't even deserve that."
After the pair sit down, Matt admits, "I should have talked to you sooner."
But, he adds, "I felt your little stunt with Vicky was very rude. Deceitful."
When Matt's ex counters that his mother Kelly paid an unexpected visit to Brittany's workplace, he continues to tell Brittany she should "be very embarrassed about" the "little stunt" with Vicky.
Brittany shoots back, "Do you think you should be embarrassed about anything?"
He replies no, and she cocks her head to the side.
"You and I have never been exclusive, never boyfriend and girlfriend, and I kept it that way because I was testing to see what I wanted," Matt says. "And you know what? I'm sorry that I didn't tell you sooner that I didn't want to date."
After they go back and forth about who blocked whom on social media, Matt calls Brittany "a child" and that's when things really start to get heated.
He says his mom and friends were right about her, adding, "You're literally full of s---." As he starts to walk away, Brittany holds up a finger: "No, I'm not done."
She follows Matt and continues to grill him about his supposed cheating. Even as Matt warns, "I'll call the cops," Brittany demands a name.
"Matt is the most vile person I've ever met," she says in a confessional. "I would love to look him in his face and tell him, 'I know you cheated on me.'"
Back in the park, the exes are in each other's faces, which Matt deems "insane" in a later interview. "I feel like I'm in Fatal Attraction," he says.
But Brittany will not be dissuaded and decries Matt because "he can't put his big boy pants on and just confirm that he cheated on me."
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I Love a Mama's Boy airs Sundays at 10 p.m. ET on TLC.