Since you seem to have tried everything under the sun, a virtual expert on the chemical approach at this point, maybe it would be useful for you to try something new. Assume that there could possibly be an emotional underpinning to your condition, (even as far back as early childhood, one you don't even remember), and Google "EFT", *Emotional Freedom Technique), then go to that website and download the manual (free) and check it out. You can subscribe for free, comes about once a week, and includes anecdotal treatments and outcomes by various practioners. It has an archive you could Search to find references to your condition.
I've used EFT for several things that worked successfully. A novice can do it, so you could treat yourself, but if your condition is particularly involved, which it sounds like it is, a skilled practioner may be more effective for you.
You can also use the website locator to find people in this area and give one of them a try. EFT is a form of accupressure that can be self-administered, or ...guided by someone who has a lot of experience with this method. Couldn't hurt, and it might amaze you if it worked and you were free of all this.