I dont really have a lot to offer other than to say I can certainly identify with your frustration. I often wish I could get an xray of my skull to see if I caused any fractures to my head from beating it the times I did.
Other than that all I can ask is if you are in therapy. I genuinely have to credit T, meds and DBT with giving me the tools to help me with emotional regulation so I dont reach that point anymore.
I wish you well.