Nothing but empathy for you here, bro. Try some drugs. Not the shrink drugs, but some psychedelics. There is some inherent risk with HPPD, but you’re already wanting to opt-out of life, so that could be acceptable. Read up on set and setting, do the prep, find someone experienced that will trip sit. And be prepared to feel overwhelmed, possibly from profound thoughts, and for some very honest introspection and soul searching. Totally okay to sob your heart out. Psychedelics are not a panacea, but they can be a tool to help you out of the local minimum.
No, just a sociopath decided to fuck with this one person’s life.