Wow, that sucks massive balls. I feel for you man. I've had that happen to me back in the SNES days with FF6 and mind you, this happened on my second playthrough. My first playthrough was from a loaned cartridge that I had to return before I could finish the game. Having to start all over again a third time was rough and rage inducing.
Usually when these things happen to me, I need to put that game and that incident way behind me, wait a couple of months until the burn has subsided, and then give it another shot. I love grinding in rpgs but they are the deathbringers in these situations.