But then I see my loving wife of 30 years who has put up with me, two kids in college who call me up for advice (not necessarily taking it, but it's the thought that counts) and a high school kid who talks to me and laughs at my jokes, good health, a decent if small home, and many, many, many friends from all the places I lived, and not really even one real enemy.
Then I wonder. Would I have been as happy if I had gotten that fancy degree? Kept that job that would have had me away on 6 week business trips twice or three times a year? If I'd not followed my dreams, even though they didn't pan out?
When I die (and at 55 it starts looking a lot closer), although I never amounted to much, maybe I'll have friends and family saying goodbye as I slip away and it will seem more important at that moment than a big job and major accomplishment. At least I can feel that maybe the world is happier and nicer a little bit because I was here. I smiled at people and they smiled back and there were two more smiles added to the world happiness account. Maybe it turned out OK not focus on career and DOING BIG THINGS.
Maybe nothing has stuck for you so far, because you haven't found what would really make you happy. Please, keep looking. Be open. Cultivate positive relationships. Help other people who are suffering. Make the world cleaner, nicer, safer, brighter, more fun, even if just through a kind word to the person sitting next to you at Starbucks, or picking up a piece of litter and dropping it in a trash can.
And if you do want to turn things around, it's definitely not too late, if you want to try again. I've had at least two great chances since I was 40. The only reason I'm not doing them now is because I ended up moving on because they weren't really what I wanted. Maybe they'll be what you want.
Most of all, don't let the world's idea of what is worth doing define how you evaluate your life. They have no idea what constitutes true happiness for you. Only you can know that, and sometimes it takes a while to find out.