Bama,
There seem to be some contradictions in our information. The statement about marihuana potency raised a red flag for me, on rechecking my information from the above website I see that the dates are somewhat different. At the end about trusting "the" process of rehab. was perhaps more of a red flag to me as not only are there more than one way to detox and quit bad habits, many rehab. processes have not proven trustworthy at all.
Yet another red flag was your figures about how many "stay clean", I have read other figures on the efficacy of the very best rehab programs being less than 15% while 5% seems to be the very best the 12-step program produces which is less than the percentage of no help at all. The figures you have been give seem outrageous falsehoods, where did you get them? Personally I think over optimistic estimates of efficacy, hurt way more than help, as do exaggerated claims of harm due to psychoactive substances. People do best when they deal with reality instead of battling phantoms with incantations.
You might find the following sites explanatory of the reasons for the contradictions.
http://www.peele.net/lib/models.html
http://www.norml.org/index.cfm?Group_ID=3374
http://www.csdp.org/
http://www.harmreduction.org/index.html
http://www.drugwardistortions.org/