none of the more naturally oriented things that @Hip listed worked for me and several of them made me infinitely worse. And fiddling your brain with monoamineoxidase inhibitors, etc, is a sort of Russian Roulette that I cant recommend.
If like me you are prone to various mental health symptoms, it can be tricky in selecting the right antidepressants. It is a very individual thing, which requires a lot of trial and error.
I took just one low-dose pill of an SSRI antidepressant called citalopram, prescribed by my doctor, and within an hour my depression became immeasurably worse, and my suicidal ideation became the most intense I have ever experienced.
The antidepressant supplement SAM-e also made me feel worse, but only slightly so.
Yet I seem to do quite well on TCA antidepressants (I have tried both amitriptyline and imipramine), although their mood boosts for me feels a little unbalanced (like part of my brain is in a good mood, but other areas of my mind are still depressed).
I also do well on MAO inhibitors, in fact even when I was healthy I found the MAO-B inhibitor selegiline (which is famous in cognitive enhancement circles) really great for generating a zesty enthusiastic mood and increased creativity.
Unfortunately I found since getting ME/CFS that selegiline makes my ME/CFS feel worse, and no longer boosted my mood, so I stopped using it. It was a mystery to me why a dry like selegiline which used to make me feel so great stopped working once I was hit with ME/CFS.
Eventually I learnt that selegiline boosts the inflammatory cytokine IL-1beta, which is a major cytokine driving brain inflammation. Since brain inflammation is an issue in ME/CFS to begin with, you would not want to increase IL-1beta and further. So I think this explains why selegiline started making me feel worse.
So then I switched to another MAO inhibitor, moclobemide, which is an MAO-A inhibitor, and I was fine with that.
I like moclobemide because in one study
on the sexual side effects of antidepressants, moclobemide came out as having the lowest risk of these side effects (only a 4% chance of getting these side effects, whereas for SSRIs, it's typically around 60%).
Another issue, especially with SSRI antidepressants, is the emotional blunting they often cause. Emotional are often blunted in ME/CFS, so we don't really need any extra blunting.
And if like me you also experience anhedonia (loss of the feeling of pleasure and reward) along with the emotional blunting, then it is even worse. Very hard to treat anhedonia.