I don’t doubt your sincere compassion for addicts.  What you want to evade here is that drug addiction will inevitably lead to self-destructive life-styles, and some of those people will die, no matter what interventions society proffers.  Doing Drugs = Death.

 
The question is not whether there will be death, but how to minimize that death toll.  When you enable continued use, rather than do everything possible to help people out of their hellish existence, you may indeed extend some addicts lives, but you guarantee that at the end of the day you will have multiplied the number of people who become ill or die.
 
Addicts breed more addicts.  Ask any high school teacher about the number of pushers lurking about wanting more kids to succumb to the pressure to ‘be cool’ – or whatever the in words are now.
 
More addicts = more women dehumanized to sell their bodies to creepy men, so they can find the money needed to fill the ‘clean’ needles.
 
Drugs and death go hand in hand.  Your sort of kindness will just destroy more people