Got to admit, I had to check the map for Eppleby! It looks tiny, I can imagine that feeling very isolating! I’m still not sure I could refer to the residents of Darlo as “real” people, j/k 😆 I hope your subsequent years in the UK have been more pleasant :)
Just to give some slight optimism in opposition to your friends, I am soon to turn 41. Its harder, but it’s not impossible. Whatever you pursue, form is everything. Poor form cannot exist post 40. Technically, I am stronger than I have ever been, and yet I’m still falling apart. Don’t consider the number, just do the work, and do it well. Good luck to you!