This will likely get buried in all the other replies and you may well have already done what I suggest. But I have to say this because it doesn't seem (from me skim reading anyway) that anyone else has really touched on this but have you been to a psychiatrist, ideally more than one? Done any research yourself beyond just the depression?

I ask because it seems like so many people just label themselves as having depression and that's it. They don't think about there being an underlying cause that has to be examined and worked on/healed, they only focus on that one depression symptom.

I'm a huge example of this, I'm in my early 30s and spent my whole adulthood so far thinking I just had depression and anxiety, that's it. A few years ago I found out I had ADHD and thought that was the answer. But it really wasn't what was causing bad feeling so much. And so over the past year I discovered I have CPTSD. Bad. A lot of trauma over my life that I wasn't aware of and living as a shame-bound person was making me feel, think and behave the way I do, for the most part. Knowing that made it so much easier to know what path to take to heal.

And in contrast to what so many others have said here, I've healed for the most part and it happened very suddenly, over the course of a month or so actually. I won't go into details as it's long and not needed but yeah it came from going through a very horrible, abusive struggle for most of the past two years. I got out of it and did had many realisations about myself and life because of it. I saw that, despite what I thought all those years, I am a strong and good person and my life is, in fact, beautiful. It's like I can hear music and see colour again after so many years without. I've never felt so genuinely happy and contended with myself and life. That's simplifying it too, I could write an essay on my experience and the difference

There's still more work to be done, of course, but I was blown away by how much change I've felt and in such a short space of time. This isn't me saying you should seek out and also go through some terrible ordeal at all, of course. I just wanted to get across the importance of looking at potential underlying causes and mental conditions, not just trying to treat one or two symptoms. And also that healing isn't always a slow, linear journey. There are people who have major depression and take a psychedelic once and they don't feel that major depression ever again after. The human psyche is a powerful and not well understood thing that has a huge range of difference from person to person