My feeling is…..that you might have made dumb mistakes, but that doesn’t make you “stupid.”
I’ve made some really dumb mistakes….but I don’t believe I’m stupid.
You’re still in your 30s. You can turn this around.
Many people have been in bad situations, but they eventually came out OK. I can understand you don’t feel like it would come out OK….but, truly, you never know what Fate will give you.
Continue with your studies of Buddhism, etc. And continue singing.