I think this is something that happens to a lot of people when they hit their 40s. Certainly happened to me, career stutters, company made bold statements about employing people with certain traits to meet made up targets, people got promoted or poached at high cost who were clearly A) unqualified and B) uncommitted. Picking up the pieces now with a likely headcount reduction of a third and you start to think, "What did I ever see in this place? Why did I even care? I don't even matter." Eventually you just do a good enough job, smile and give thumbs up when they survey morale, whilst half muttering under your breath about Nero, Rome and fire.
Guy at our place just up and left at 51 last year, became a joiner. Think he had nearly 30 years with the company too. Doesn't regret it one bit. What I would say is check the balance, for you. We all have to work in today's society, well most of us, so it's about balancing getting enough in vs doing something that doesn't send you insane vs following your dream. I know people who have started their own businesses, a dream for years, and ended up hating it and saddled with more debt. But I also know people who earn a living just off eBay and never seem to have money concerns.
Although the molecules that make us up come and go, your consciousness that makes you you only gets the one ride around, and 99.9% of us won't even be a footnote in the most insignificant annals of history, but that doesn't mean you can't enjoy it whilst you're here.