This is for me an eloquent reflection on saying goodbye to the dreams of youth. I have for several years considered how the dreams I had in my teens and twenties were not realistic dreams. The idealism of youth was not even something I particularly valued at the time but no matter how practical and realistic you THINK you are there is nothing like actual life to disabuses of ideals and idealism you don't even think you have. There are times when I think that "realists" are people who have decided that your dreams are more worth giving up than theirs are yet who do not realize the impracticality of their own dreams.
At length I settled on the idea that a dream can help you work through life provided it is not the goal of your life. Whatever dream you have will ultimately fail to satisfy and at the end there is always death. As Koholeth puts it in Ecclesiastes, even if you attain fame, honor, and riches and achievements you still die and then who knows whether the person who inherits what you labored for will be wise or a fool? If we talk here about Solomon something suggests to me that he began to sense his sons were not going to lead the kingdom in a good direction. The kingdom of Israel was already in danger of dividing as early as the reign of Saul. Unity was easy during financial prosperity and with leaders willing to accomodate for the sake of unity (and in Solomon's case very quickly killing off anyone who was a threat both to his rule and to the unity of the kingdom).
A mid life crisis can happen at any time and any age, what is most frequently called "mid-life crisis" at any rate. All that is required is for your dream to run into reality.