without knowing the specifics, im gonna make a generic guess: she probably begins to realize that what she focused on during those years are not what she now realizes matters more. And she figures its probably not possible to perform a course correction at this point. I will no doubt be downvoted to oblivion for saying it, but this is becoming an increasingly big thing, in the next 10-20 years it will be an order of magnitude worse than now.
I mean that’s just growing up. I’d love to be a teen again with the life experience I have now. But that’s just a fantasy of course, nobody gets to do that.