Couple of thoughts:

The fitness industry is about a lot more than being a trainer in a health club. From my experience most health club trainers are not respected or terribly qualified ( weekend certification). Now, degree and nationally certified trainers have a lot of options open to them, from studio work to partnering with physical therapy... but all this requires a significant education investment.

I see no mention of meeting with a career counselor or life coach to have someone objective help you analyse your skill set and experienced. That might be something to consider. There might ideas there that would be a good fit to explore.