Sorry, a sample size of one does not make a drug "safe". The fact is, there's no such thing as a safe drug, as everyone's body reacts differently to each one.
> although none are as destructive as alcohol.
Really? Are you really saying that heroin, which is one of the most addictive drugs in the world, is not as destructive as alcohol? While there are more alcoholics than horse heads, that's because there's more people that drink alcohol as a whole. Are there any studies for the ratio of abusers/users for heroin and alcohol?
> Nicotine is another extremely addictive substance.
The difference being, nicotine's psychoactive effects are minor compared to hard drugs. People don't die from a nicotine overdose.