> Yet, somewhere six or seven years into my practice, whatever progress I was making petered out. I was experiencing a growing sense of bodily agitation and began self-medicating with drugs and alcohol. Looking back, it was also during this time period that I had my first dissociative experiences, in which elements of my sense of self became separated in a way that impaired my ability to function.

Lots of good discussion in this thread on how meditation can lead to problems, particularly intensive sessions like retreats, but I think it's important to highlight this paragraph from the article.

If we accepted that meditation can induce alterered states of consciousness, like various medications can also do, it seems dangerous to wantonly start mixing such things without rhyme or reason. Dissociation seems almost inevitable.