I've been following this thread but keeping quiet. I don't know why it's been hard for me to post, but your story really speaks to me. I suffered from depression and chronic fatigue for pretty much my whole life, kind of hitting rock bottom last winter and coming close to suicide.
I explored the psychological and spiritual routes extensively. Massage, reiki, cranial sacral therapy, counselling, psychotherapy, yoga: they helped me understand myself, but I was still depressed. I tried every diet you can imagine: veggie, vegan, low carb, no carb, fasting, all you can eat. I followed my dreams, had a crazy social life: still depressed.
Anyway, long and short of it: after a lot of research and experimentation I got a full hormonal panel done. I was diagnosed with a hormonal imbalance, went on medication and guess what? The depression is gone. It only comes back when a certain hormone dips too low.
The medical industry does not understand what depression is. They say "it's a chemical imbalance" - but what does that really mean? What I've learned is that depression is a symptom that something is not right within our physiology. In my case it was hormonal. I'm willing to accept it could be something else for somebody else, but personally I think it all comes down to hormones. I can't believe how much even little things (like my perspective) have been effected by hormone treatment.
That's not to say there isn't a psychological component to depression. I believe it begins as a mental state, and as this becomes chronic, the negative way of thinking impacts the body, makes us sick, and our sick physiology makes us feel worse. We then go to treat the mind (therapy) but not the body. Or, if we do treat the body / brain, it's with the wrong drugs. It's ridiculous to put people on SSRIs without checking their serotonin levels first, and yet I've never heard of a single doctor who's done that.
So, my advice is: get your hormones checked (I should make this my sig at this stage ). Your blood is objective: your blood will not lie, and knowledge is power.
I've been reticent to write here because it feels strange to assert that I've got the answers. I'm definitely not out of the woods yet - I still have bad weeks, but overall I know I'm heading in the right direction. I feel like I should be angry that I wasted so many years of my life being depressed but... honestly... even the most terrible times I went through seem worth it now. Life is so beautiful, and I'm so glad I stuck it out. You'll get through this, and you'll be glad you did.
"I think the basic anti-aging diet is also the best diet for prevention and treatment of diabetes, scleroderma, and the various "connective tissue diseases." This would emphasize high protein, low unsaturated fats, low iron, and high antioxidant consumption, with a moderate or low starch consumption.
In practice, this means that a major part of the diet should be milk, cheese, eggs, shellfish, fruits and coconut oil, with vitamin E and salt as the safest supplements."
- Ray Peat