Amber Portwood
"Teen Mom" alum Amber Portwood and daughter Leah, 5, on "Being Amber." MTV

“Teen Mom” alumna Amber Portwood, the original bad girl of the MTV series, expressed regret during her “catch-up” special. The 23-year-old returned home to Indiana after her release from prison in November. Reconnecting with her daughter Leah, now 5, has been heartbreaking for the troubled reality star now that she realizes how much time she missed with her little girl and how her incarceration affected her only child.

“Being Amber” is set to air on MTV Sunday at 8 p.m. EST, but a clip from the emotional episode, which was posted by Us Weekly, shows a sobbing Portwood regretting her choices. "I feel so f---ing bad," she says, crying, as Leah listens on the other side of the door. "I left her for so long. ... I know why she's acting the way she is. She's afraid that I'm gonna f---ing leave her again."

"I just f---ing hate everything I did," Portwood tells an MTV producer from behind the closed door. "It was all the drugs and s--t. It was all I did. All I did was get f----ed up."

But Leah had heard enough. Finally, she opens the closed door and rushes to her mother’s side as she tries to make her mother's tears subside.

It wasn’t that long ago that Portwood confessed to Dr. Phil McGraw she was high “every time” she filmed “Teen Mom.” She agreed to have a judge send her to prison after rehab stints failed to treat her addiction to pain pills.

The emotional clip from “Being Amber” has been provided; check it out here.

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