Your suggestion to get our subject weaned off antidepressants reminded me that antidepressants can do the exact opposite after an unspecified period of time. This dramatic change might have triggered the ability of the body to neutralize and reverse the effects of this antidepressant.
Sleep is not possible if the Hippocampus isn't fed with Choline. So have some organic poached Egg Yolks, and drop all Sugar in case of a Candida populace in which the weak ones are croaked with the tough ones now snorking up greater rates of Magnesium. It's a shot in the dark but worth a try. I would supplement with the Candida killer, Caprylic Acid, a derivative of Cocoanut Oil.