Part of the problem with prohibition is lack of safe access to medical quality marijuana. For those of us who live in a non-medical state, the ability to safely access marijuana for medicine is even more elusive; and the availability and afford-ability of the correct quantity is a "pipe dream."
With every medication I have ever taken, the doctors have always told me to take the dose as prescribed and do not stop the medication without weaning myself off slowly. To do this with marijuana in a non-medical state is impossible. In reality, there is no way to provide myself with the amounts needed to consistently take the same dosage each day. And when what I can procure runs out... sometimes there is no telling when or where the next dose will come from, or if it is even of medical quality.
So I sit here with my pipe, and dream of the day when I will be able to walk into a pharmacy with my prescription and receive my medication like the other millions of people on this planet who require daily dosages of drugs to get through their lives.