A British coroner revealed in October that the Grammy-award winning singer, Amy Winehouse, had died of alcohol overdose. Apart from battling drug and alcohol addiction, the 27-year-old singer reportedly had suffered from an undiagnosed mental illness too.

Amy was found dead at her London apartment on July 23.

According to a Daily Star report, the "Back to Black" singer may have been struck down by an obscure illness - Borderline Personality Disorder - which leaves the person emotionally volatile coupled with feelings of anger, emptiness, shame, guilt, thereby pushing him or her into substance abuse and eating disorders.

A family relative said that the multi-talented singer and songwriter may have suffered from the undiagnosed mental illness.

"It was never diagnosed, because unfortunately she would never agree to a proper diagnosis," the Daily Star quoted a family member as saying. "I'm not an expert, but from what I've read on Borderline Personality Disorder it kind of fitted with her."

Meanwhile, 61-year-old Mitch Winehouse, the father of "Valerie" singer, wished his daughter had sought counselling.

"She never stopped trying. She hated the way she was when she was drunk and when she was ill," the Daily Star quoted Mitch as saying.

"And you know, the way I look at it, she died trying."

"She didn't give up. She died trying to make herself better," he added.