One of the things that's too often overlooked is that subtractions might do more to help than additions. If you're taking a host of vitamins, herbal remedies, and strange supplements and still feeling like shit, it's likely because all the medicine in the world won't heal if you're still taking poison.
Not to be that person, but I am fully convinced that eating animal products plays a decisive role in depression and other mood disorders. Not only is there science pointing in that direction, but it matches my own personal experience as well as what every other plant-based person I've known has experienced as well. Before the switch I was so far in a constant background noise of depression that I was ambivalent about whether I wanted to live or not.
I've tried a lot of things, with only ever small or temporary results at best. Going plant-based, within weeks of staying consistent with it, marked the first time in my life when I actually began to actively want to live (even in spite of our capitalist hellscape). That desire to live has endured since then to the point that it's tempting to say I might be cured of depression.
Perhaps you had an imbalance of vitamin a. Plant based vitamin a (beta carotene) is safe and can't really be overdosed. Plant based diets tend to have more vitamin e in them as well, and vitamin e sort of counteracts vitamin a.