Yeah, well as much as I have no love for users of heroin, speed, crack, coke, meth etc, most of the above scenarios relating to the destruction of the family unit can, and have, also been attributed to alcoholism.
So is the choice of drug the problem, or is it more to do with the laws? Here in Oz we righteously look down our noses at drug addicts as "scumbags", but consider alcoholism an illness deserving at least modicum of sympathy.
If all drugs were decriminalised, readily available and regulated by the government, it's a reasonable assumption that drug related crimes would diminish exponentially.
Prohibition in the US created an enormous spike in the crime rate at the time, and the only way to reduce alcohol related crime was to decriminalise alcohol, so maybe we should take our heads out of the sand and accept that one drug is probably as bad as another, and either ban them all, or make them all legal? Just my opinion, of course.