I know not why there is such a melancholy feeling attached to the remembrance of past happiness, except that we fear that the future can have nothing so bright as the past.
I have been thinking about the notion of perfect love as being without fear, and what that means for us in a world that's becoming increasingly xenophobic, tortured by fundamentalism and nationalism.
We have perhaps a natural fear of ends. We would rather be always on the way than arrive. Given the means, we hang on to them and often forget the ends.