NEW YORK (AP) - R&B singer Mario has been dealing with drug addiction most of his life - not his own addiction, but his mother's. The Grammy-nominated singer, best known for his 2005 No. 1 hit ''Let Me Love You,'' invites viewers to take an intimate look into his struggle to save his mother, Shawn Hardaway, from her dependence to heroin, in the /MTV/ documentary ''I Won't Love You to Death: The Story of Mario and His Mom,'' airing Sunday.

Mario, 21, began filming the documentary in the summer while working on his album ''Go'' to be released Nov. 27. It is shot from Mario's perspective - revealing a balancing act between a blossoming career and a turbulent personal life. ''It's a documentary showing the relationship with my mother, and her obstacles that she had to overcome as an addict, a drug addict. She was addicted to heroin most of her life - she's clean now,'' Mario told The Associated Press in an interview this week.

Sobriety came after Mario - with the help of Hardaway's boyfriend, a close family friend and an interventionist - confronted his mother on camera, offering her the chance to reform her life. She accepted. And Mario says the last three-and-a-half months have been the best in his life.

Addicted to heroin, Hardaway was unable to care for Mario during his early years. But it was her - a pianist - who sparked Mario's passion for music. ''She had a lot to do with me acknowledging music in the first place. She kept good music around,'' said Mario. ''She was the person who encouraged me to do those talent shows, and ultimately allowed people to see my talent.''

But it was Hardaway's addiction that kept her son from wholeheartedly enjoying his successes. And it was her addiction that led to a short childhood. ''I was about nine or 10. I remember seeing needles on the dresser, and her with like - I can't remember if it was a belt - something around her arm and she was just like, sleep on the bed,'' said Mario. ''That was the first time I ever noticed anything weird and after that it was just, I guess, her personality and her mood swings, and that type of thing. And just her not being around for long periods of time.''

Later, Mario, who has appeared in the films ''Step Up'' and ''Freedom Writers'' found himself doing another kind of acting - playing the role of parent to his mother. Mario's decision to stop supporting his mother's lifestyle is what led to the intervention.

Mario said being on camera was very difficult at first. ''I didn't want people to see how I was sometimes aggressive with my mother, or sometimes I would have to raise my voice or I would say things that I really didn't mean,'' he said. ''It was really difficult but it got to the point where I felt like the camera was almost like a book. I was telling a story. I was releasing all of these feelings that I had inside for so long.''

He said that both he and his mother hope their story is one that others can relate to. ''I was kinda surprised because I didn't know so many people had gone through the same thing. It kind of uplifted me a little bit more. And I really felt good about it. And I feel like it's gonna help to save some lives.''

Source: Associated Press