I looked it up on Wiki because I saw someone else mention it before. Don't get me wrong, I thought she was better than Steps but some people seem to be slightly overstating what impact she actually had on the music industry, which wasn't really much at all.
Actually she had a massive influence on the industry. Before she came along there hadnt been a female vocalist like her for years, she is in the mold of Dusty Springfield. She wasnt manufactured she had an honest true and unique voice.
After her success we get people like Corinne Bailey Rae, Duffy, Adele and so on. Now you can argue that they would of made it without her kicking the door down first, but I would say not, the reason they were given a chance is because Winehouse had made being a solo female vocalist popular again and so the industry was looking for similar artists. Same way it always works, its fad and money driven, Oasis make it, they are all looking for an Oasis type band, the Beatles, they are looking for Beatles type bands, Elvis etc.
Her output doesnt match her talent, but thats due to off field problems, her talent and the uniqueness of her voice actually put her up there with the likes of Springfield & Billie Holiday, its a shame her output wasnt at the same level, but then what she did put out was always quality, there is nothing poor or substandard about her work at all.
As for people wondering about why take heroin, well there are loads of reasons, it feels fucking great for a start, otherwise no one would do it, it feels so good in fact it becomes all consuming. I've never done it but I guess thats the reason, and its like anything in life thats a thrill, why do we do anything, why do we watch football, because we are addicted to it and sometimes it feels fucking great. Ok its not a self destructive pursuit, but then look at other things, sky diving, rock climbing, speeding on the motorway, there are a number of things people do that have a massive edge of danger to them, they do them because of the thrill and because they dont think they are going to die, most people who get into stuff like heroin dont think its going to kill them, they think they can handle it, despite the warnings and everything they know.