I think you're also falling a bit for one of the common fallacies people who have midlife crises have, the idea that there's something wrong with changing the direction of your life at 40, that it somehow means you've failed.
Having helped a couple of people going through that sort of phase, a pretty useful tool I found was to have them think about how much the world has changed in even just 20 years. So, given that, it isn't really that big of a deal that at 40 you might want to do something completely different from when you were 20, simply because your current life is almost entirely different to what it was 20 years ago.
We're long past the times when several generations of people would live and die doing the same thing without seeing any meaningful change in lifestyle and so it isn't that big of a deal if that also reflects in our own life choices.
Having helped a couple of people going through that sort of phase, a pretty useful tool I found was to have them think about how much the world has changed in even just 20 years. So, given that, it isn't really that big of a deal that at 40 you might want to do something completely different from when you were 20, simply because your current life is almost entirely different to what it was 20 years ago.
We're long past the times when several generations of people would live and die doing the same thing without seeing any meaningful change in lifestyle and so it isn't that big of a deal if that also reflects in our own life choices.