“Teen Mom 2” star Leah Messer admitted she used prescription drugs to alleviate pain, but denied her stay in rehab was to treat an addiction to narcotics. Hours before Season 7 debuted on MTV Monday night, Radar Online rolled out a story that claims her ex-husband, Corey Simms, thinks Messer is back on drugs and refused to film some scenes because “Teen Mom 2” producers ignored her alleged drug use.

“Corey feels MTV did him dirty,” an insider told Radar Online before the premiere. “He thinks they had the perfect opportunity to show viewers, ‘This is what happens when you get on drugs, this is the reality.’ Instead, they made it seem like Corey was constantly attacking Leah for no reason."

Messer, 23, was caught slurring her words and nodding off with her daughter from a different marriage, Adalynn, in her arms last season. Simms and his wife, Miranda Paterson, openly accused of her popping pills in Season 6.

Since MTV didn’t do anything about it, he wants to limit his involvement in the show. “Corey told MTV just what he thought about the situation, and said that he and Miranda would not film nearly as much as in past seasons,” the source said. “Producers understood.”

The former couple share 6-year-old twins Ali and Aleeah. Season 6 left off with Messer refusing to talk to Simms about their girls since he brought Paterson to the rendezvous. “If he can’t talk to me for our children then I’m not doing it. I’m not going to be put in another situation where I’m ganged up on,” she said.

Messer, a native of West Virginia, admitted taking Hydrocodone, Percocet and Tylenol 3, which was prescribed to her after she had complications with Adalynn’s birth. When she went to rehab last year, she said it was to treat depression and anxiety.

The "Teen Mom 2" Season 7 premiere airs Monday at 10 p.m. EDT on MTV. 

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