I don't really have an answer- just my own experience. I definitely find that stress exacerbates my symptoms, but, at least for me, stress is not the root cause.
One point of interest: I had oral surgery in June and took Tylenol with Codeine, and for four beautiful days while on the meds, I didn't feel any burning at all. Go figure. I don't know if antidepressants are comparable to painkillers, but I suspect it operates on a similar principle with feel-good brain chemicals.
That being said, if you suffer from clinical diagnosed anxiety or depression (I do not), then the drugs may indeed be helping you out. If not, I would be skeptical, and would want to make sure that there is not masked damage going on in the meantime.