Hang in there, man. You are doing great work, and I know what it's like to feel discouraged and depressed. We've all been there, and most of us have war stories and/or wounds. You'll get through it, and feel free to vent here anytime!
That said...
My advice is to take a walk, leave the project for a week and come back refreshed.
Don't take harmful prescription drugs...
This attitude frustrates me. ACTUAL mental illness (not just being down or having an off week) is just that: an illness. Your brain chemistry is fucked up. Your neurotransmitters do not work the way that they are supposed to; you do not absorb chemicals that you need. You can't just "make it better" and the only reason people think that you can is that there is a cultural stigma attached to mental illness. It's insane (no pun intended); people have no better control over, say, an autoimmune disorder. We don't look down on people with lupus for taking meds to keep their body from destroying itself, yet we DO with people with mental illnesses. People get frustrated, I think, because medications maintain, rather than fixing the illness, but again, comparing to autoimmune disorders, right now there is no cure. That doesn't mean treatment is a bad idea.
As far as medications, it is a long road. Part of the issue is, again, the diversity of brain chemistry. A single diagnosis (let's say bipolar disorder) can really mean a myriad of chemical imbalances with the same result in behaviour. This is why there are so many different kinds of medication, and it is a process finding what works for each individual. The science has come a long way, but there's a long way to go. I've seen a lot of people in various stages of treatment. I know those for whom medication A worked fine (ie, not constantly zombie-like, still creative, and more functional than they have been) until they changed other medications, and then medication C was the right answer, but they didn't know until they tried medication B. I know others who are afraid their creativity will "go away", and they define themselves by their illness, so only "self-medicate". I have yet to see an instance where it's a good idea, and where they weren't MORE productive when seeking help (though many cases of wrong medication, and rather than talking to their doctor about it, just stopping taking it and ending up back in the mess they were in before).
I know for many people, this attitude is rooted in mistrust/dislike of big pharmaceutical companies. I can understand that, and relate to that. Things are expensive, but then, so is years of research and development, testing and Federal approval. All of these things are far more complicated than working at McDonalds, and when we're talking about mucking about in people's wiring, VERY important that it is done safely and as well as it can be done. On the business end, there are lots of sleazy practices, but when it comes to the medication, I believe that the people developing it really DO care about making people better. Furthermore, it is capitalism at its' most basic. If a medication is harmful or ineffective, then people will not buy it. Developing something like that is poor business at best, and very illogical.
Of course, some of my perspective comes from being in Pittsburgh, which has some of the finest mental health facilities in the country, more so for providing all sorts of assistance for those with low income (often those who need help the most).
Hearing this sort of attitude over and over is like telling someone with a broken leg to walk it off.
...append to this a rant echoing rayw's sentiments about "all natural" (arsenic is also all natural!) and don't even get me started on the whole "raw foods" movement.
Bah, I'll stop now and apologize. As you can see, sort of an issue close to my heart