I think those born with an addictive personality can live thier whole life very happily if they never do drugs, alcohol and other substances.
But once they've tasted whatever it is that fills the hole inside them, life will not be the same. Even after getting clean and sober, the recovered addict will feel like a mountain climber standing on a four inch ledge... never able to be completely sure ...
The only way to live from that point forward is to always remember your grave, and to be thankful and appreciative of all the worthwhile things that you do have.
I think this is especially true for heroin users. You can tape that little monkey's mouth shut, but it will always be there, hanging on, waiting...
It isn't my intention to steal hope away from anyone, because obviously there can be fullfilling life after addiction. Its just different, and it requires a deeper committment to truth. The 12 steppers I know are the best friends a person could have - definately not shallow people.