I am retired and probably more content in some ways at 63 than I ever have been. I have led an interesting life, had some good jobs, have travelled, renovated a house with my husband (not using builders!). Have always been somewhat short of money but have not aspired to material things very much, so have had enough to lead the sort of life I wanted and to educate my son.
Have never, ever held any real career ambitions and have never ever hankered after being rich and successful or famous in any way. I need money to have a roof over my head, to eat well, be warm, be mobile and travel occcasionally. If I had any more it certainly wouldn't make me happier.
Some of the happiest people that I know have lived all their lives in the same place and done, what some would call 'nothing' with their lives. But they are content and that is what life is about.
I certainly don't miss being out in the working world. It is just wonderful being able to do what I want when I want to do it and not being under any pressure!
Good luck to you. I hope your health continues to improve.