Leah Messer dropped a bombshell during an intense sit down for the MTV "Teen Mom 2" reunion special. The reality star vaguely confirmed rumors that had been circulating in the tabloids that she had an affair with her ex-husband Corey Simms while he was married to his currently pregnant wife Miranda, Us Weekly reported. Messer admitted that she did something in the past that disrespected Miranda as Corey's wife.

Corey told Messer that Miranda helped give him a backbone to stand up to Messer, as previously reported by HNGN. But when Miranda was invited onstage to discuss Messer's and Corey's co-parenting skills, she couldn't help but call Messer out on her actions herself.

"Miranda, I'm not familiar with what happened between you two to build up all this hostility," Dr.Drew said, intervening between the two women.

"There's a lot," Miranda said, "mostly the disrespect to me as a person and that this is my husband. She's disrespectful to my marriage."

"There's still an overlap, where you guys still kinda together when Miranda hit the scene?" Dr. Drew asked. He gently hinted at tabloid rumors that claimed Corey cheated on Miranda with Messer, as previously reported by In Touch Weekly.

An anonymous source told In Touch back in September that Messer and Corey had sex in his work truck when they were supposed to meet to discuss their twin daughters, Ali and Aleeah. It's not clear when the affair took place.

"Things happened that shouldn't have happened and it was disrespectful to Miranda," Messer admitted during the reunion special, "and I have apologized."

"And she's let that go," Corey added. "Me and Miranda's moved past it."