Im stuck and I cannot move....i dont know where I am?

The point is that now you are on a different journey and you can excel at this one just like you did at the last. You had the courage and the will to take yourself from that frail young boy to a champion, well, now take yourself from an injured champion to a ........whatever you can dream of becoming. You mentioned a book- there's something positive. You wrote music, that's an outstandingly positive outlet and creative path. Find a new path and follow that. If you can't do your old job in martial arts, maybe there is something you have learned that you can use to form a new dream. If that frail boy could do it, so can you.