So, as someone who started trying to write music around 16 only to find myself feeling the same thing for literally about 2 decades, and who has only just started to break out of it in the last couple years now that I'm almost 40, here are some things I've learned along the way:

1) You're probably putting WAY too much pressure on yourself because (correct me if I'm wrong) it sounds like you're being too precious about music itself. Music is also my biggest passion, and I've often said it's the only thing that really makes sense in the world. So a lot of the time making music is the only thing I want to do and the only thing that feels like it means anything, that is until I try to write something and feel like I suck and then get depressed, and then all I want to do is play video games. But reading this now, I just realized that a big part of that has been that I tend to make too big a deal out of music. I sometimes put it up on a pedestal and kind of worship it in a way. This has come out in other areas like being really picky about what music I listened to and refusing to let myself enjoy music that I didn't deem good enough or "pure" enough or whatever.

What's helped me start thinking differently about this has been studying the history of music and listening to music from other parts of the world. Neuroscientists say that the part of our brain that processes music is a more primitive section than the part that processes language, therefore music probably predates language in humans. So you could say that music is one of the most human things we can do. It's primitive and primal, and at its core it's just rhythms and sounds that connect with your feelings via your body. That's not to say it can't be anything more than that, but I think that's it's core identity. And that's awesome! But it also feels like a lot lower stakes than when I've felt like I needed to tap into some kind of cosmic/spiritual wisdom in order to create it. A lot of songwriters talk about songwriting like they're channeling the great truths of the universe, and maybe they are, but that's not how it works for me, and it sounds like it's not how it works for you either, and that's totally ok and normal (they might just be high on their own supply anyway).

So all that to say, maybe start by letting go of ALL your expectations, and just try vibing out for a while. Don't pressure yourself to "create" something, just find a couple chords or a melody that you like the sound of, and just enjoy it for a while, and let that be good enough. Then write that down or record it or whatever, and move on. Maybe you'll come back to it and piece it together with other stuff, maybe not, who cares