Hello neutrino: Well... for what it's worth... I'm in my late sixties! And I still don't know what life is about. And, in my case, I'm still confused about my gender identity. Personally I don't think most people live in this type of existential crisis. I imagine that most people simply hold to some mostly unexamined beliefs & live their lives day-in & day-out. I imagine that there's just a select few of us that exist with this continuous undercurrent of turmoil. Perhaps I'm wrong. (I probably am...)

I have certainly struggled with depression & anxiety (as well as my gender identity dysphoria) my entire life. I can't recall a time when it wasn't all with me. I don't know if the types of thoughts you describe are a sign of depression. I don't feel particularly depressed at this point in my life... at least not in the sense that I can't get out of bed. I do get up & do what needs to be done each day. But I also don't take any pleasure in it. It's all just something that has to be done. So I do it. Perhaps that is a variety of depression in its own right. I don't know.

Anyway... I didn't have any great insights to offer you here. But reading your post I thought that a lot of what you experience is quite similar to my experience. So I thought I would share my thoughts. I wish you well...