I'm seconding Valentijn here, Cath.
Based on your other recent posts here at PR, I think you may still be in the denial stage. You have a very serious illness that is likely to get very much worse if you don't manage it correctly. I suggest that you do a lot of reading here at PR to get a better understanding of the illness before you try any exercise program, or extensive travel.
Dr Klimas has some videos out -- maybe someone can give us a link -- on how to exercise with ME/CFS. I expect you will be shocked at what is considered appropriate exercise for people with our illness. I very much doubt you are going to find a trainer or exercise physiologist who has even the slightest clue about appropriate exercise programs for PWME, particularly in the UK.
PS Many of us were athletes or very active before ME/CFS hit. We understand what you're saying about exercise; we want to exercise, too, but we've discovered the hard way how much damage we can do by not treating our bodies correctly in the early stages of the illness.