Have you tried free/automatic writing? I don't know what the term is actually, but just stream of consciousness, putting words to paper, zero filter or pause, straight from the brain.
I usually start with "I don't know what to write but" and then just don't let myself stop. I have to keep putting words down, only rule.
It sometimes starts or turns gibberish, but eventually I hit a flow and real stuff starts to come out, and then I'm just writing.
I've seen the concept applied to art/drawing as well. I highly recommend trying!
Quick edit while I can: after googling this there's a lot of woo/spiritual stuff about it. I don't really subscribe to that, I just think it's a great tool to get out of your head and enter the flow state of writing, when it feels inaccessible.