Vicar - I have not "poked at someone's hurt" and was not talking about you when I referred to people who are unable to discuss it due to having been hurt. I was talking about people like MaryZ who say they suffered due to people around them being addicted to drugs, who are now telling people on here to respect their hurt and not point out that some of their assertions are incorrect.
"Do we absolve ourselves of all decency on this board then?"
MaryZ is the one who called me quite a few names, including "arse". What do you think I have said that was indecent?
I am very sorry about your sister. I really am. I cannot imagine losing my sibling to such slow decay over many years.
However, I will still say that my experience and of many others I know personally shows that it is entirely possible to recreationally enjoy many substances just like one enjoys a glass of wine several times a week.
This is why I asked MaryZ what she thinks about alcohol: Alcohol is more addictive than most drugs. If you think all recreational chemicals are evil, people should be forcibly prevented from, and if that fails, prosecuted and punished for their use, how do you square that with the open acceptance of occasional enjoyment of wine or beer with friends? Serious question. I would appreciate an answer to it.
"comparing my alcoholic brother, with my drug addicted sister, i would say yes, both are bad, but one brought noticeably worse effects than the other"
Perhaps for your family.
"ive never come across someone who could just use heroin at the weekend."
I haven't either, but that is because I don't associate with idiots. I'm told that there are many recreational heroin users (who don't inject it).
"i dont see people dying because someone sold a bottle of wine that wasnt from their usual supplier"
In the very rare instances that happens, it is the fault of the Prohibition, not the recreational chemicals themselves, most of which are quite incredibly safe in usual doses.
"if they were legal, how many more people would use them, and suffer those ill effects?"
There is an important point here imho: Adults should be free to consume whatever they want without harming anyone else. You do your own risk/reward assessment and go mountain climbing and bungee jumping, for example, without asking for the government's permission. You are able to buy cancer sticks cigarettes and slowly poison yourself into an early grave. You should also be able to have some fun playing with your brain chemistry, if you know of the risks and accept them, considering that most of these substances are not as addictive or even harmful as cigarettes.
There are already many millions of people using recreational drugs in the UK and the fact that there are so few reported "ill effects" should give you an idea about the level of "danger" here. (I remember the London club I went to in 1999 or so, where I asked for a beer and bartender said "Why?". Everyone else was on bottled water 
)
From what I have seen and experienced, the danger is when people start using them at an early age, when their brain is still developing. This is when you have problems of addiction & intelligence/focus/psychoses. (Same with cigarettes, really - early starters have the most difficulty with quitting because nicotine is deeply wound into their brain chemistry).
As I said before, I would like drugs legalised and a minimum age of 30 imposed on their sale and use, with regular testing and severe penalties.
For the record, I don't use drugs so it is not for my benefit that I would like them legalised. This is because I see that prohibition is not working and believe that this is how freedom of choice for the individual and prevention of harm for the society can be achieved together.