There are many possibilities, such as love, the world situation ~ ~ The author writes in a rather secretive way, or it may be that the author uses the frustration of writing about love to vent his disappointment.

in love, this sentence is about being fascinated by a beautiful woman, dreaming and pining for it;

In terms of worldly affairs, this sentence means that worldly affairs are complicated, but they can't be solved, leaving only sorrow.