The point that's being made here is that yes, cannabis can make a tiny proportion of users suffer. This is no different to ski-ing holidays or peanuts. Some people *die* from peanuts, which doesn't happen for cannabis.
I have a friend who has to carry an adrenalin injection everywhere with her and cannot eat any pre-prepared food for fear of peanut contamination.
Yet who among peanut users really needs them? Is our enjoyment, that could be so easily got elsewhere, worth the suffering of those who are severely allergic? Could you stand in front of a peanut death and tell the parents that your enjoyment of peanuts is worth it?
More than this, there is also no evidence that criminalisation reduces use, or conversely that decriminalisation increases it. In the Netherlands, use went down for six years after decriminalisation, then only went up at a similar rate to prohibitionist countries. Their use is around half ours.
When the UK government downgraded cannabis, use went down. But, more interestingly, it was already going down beforehand. Classification makes no difference.
What criminalisation does do is keep production, supply (and profits) in the hands of some of the most unscrupulous people imaginable, it gives criminal records (and thereby all maner of life ruination: careers, adoption, you name it) to otherwise moral law-abiding people.
I'm sorry that your friend has suffered. Nobody has said these drugs are harmless. It is precisely because there are dangers that they should be controlled. The suffering of a tiny minority doesn't justify prohibition for cannabis any more than it does for peanuts.
