I have spent most of my life wanting to write and yet blocking myself in some capacity - and this is despite having spent 5 (lo-o-ong) years doing a PhD. However (and please disregard any or all of the below if it is not helpful for you) the thing that has (recently) helped for the first time has in fact been my horse-riding.
( Cut for LENGTH...! Lol! And Writerly Navel-Gazing! )
So, for me, taking this approach has led me to a whole new place in my writing, where I am actually enjoying being at the computer, which is the first time I have EVER felt that. It's still a work in progress, still a process of noticing what works and what doesn't and negotiating the inner voices, but I have faith in myself now, and I'm having fun!