In a sneak peek for the upcoming episode of Teen Mom OG, the couple fought when the mom of Leah, 7, refused to get married in Las Vegas while in town for a friend's wedding over this winter.
"I just want Leah by my side!" Portwood, 27, argued to Baier, 46, after a phone conversation with her concerned brother Shawn.
Baier said he understood, but then vented to a producer in a bizarre rant.
I will not marry her, ever!" he hissed. "I'm not going to let her brother dictate my life."
"She wants to marry her brother, that's who she wants to marry!" he continued. "F**k her, she just humiliated me on TV. I'm done!
As RadarOnline.com exclusively reported, Portwood broke up with Baier when he failed a lie detector test she told him to take regarding cheating rumors.
"She is saying it's over," a source close to the couple of three years said. "But they could get back together. They've gone through lots of ups and downs."
Portwood has said she doesn't trust her man — and it's not hard to see why.
As Radar revealed last year, Baier has a whopping nine children with seven women, but initially told Portwood he only had two children. Five of the women sued him for unpaid child support in Indiana court, but the cases were dropped.
He also hit on Portwood's Teen Mom costars Farrah Abraham and Jenelle Evans before settling for her.
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