Thank you for your replies

I don't think I can respond in multi-quotes?
anacrusis: I don't have a "current life" to obliterate tbh, only savings. But yes, I need to figure out a middle ground and try to avoid falling into the "let's blow all my savings on this idea" trap, which just scares me out of doing literally anything. Finding a steady job to get me out of this current rut and then adding in gigs around it in the first instance sounds a sensible way to go.
Dino: I did enjoy teaching piano many years ago. It's state school compulsory education that I find a physical and psychological drain (UK schools have a huge staffing problem right now, everyone's quitting!). I imagine I'd be good at programming based on my music and language skills, and if it's flexible/well paid so allowing me to dedicate time to piano then it's a good suggestion. Thank you!
ego0720: I definitely don't see getting back to piano as some magic solution to all of my problems. But at the same time I know that giving up music was when everything started to go wrong for me, and I've discussed this in depth with a therapist. I'm working on not dwelling on that past decision, and part of that is asking 'right, what can I do about it in the present?'. I respectfully disagree that music is just personal enrichment, but I take your point about needing to be of value to others. For example, if someone comes to you for lessons then you are doing something of value to them (I love teaching, just not in a formal classroom context). I used to spend all of my time making piano arrangements, but they were all things I personally wanted to play and I suppose if I channelled those talents to film/game arrangements there might be some money in that (not a substantial income but people do buy that stuff!)