In literature, poets miss their loved ones, but write that their loved ones miss themselves. What kind of writing is this? What's the role?

This writing is called association, and in ancient poetry it is called the combination of reality and reality.

A common example is Li Shangyin's Notes to Friends in the North on a Rainy Night: "Cut the candle at the west window and talk about the rain at night." It is this combination of reality and reality that is adopted. There is also Bai Juyi's "Going home at night on the winter solstice in Handan": "Sit at home late at night, and talk about people who travel far away." This is also the case.

The function of this writing technique is to write about family members and their thoughts with imaginary scenes, and to set off their homesickness, homesickness and homesickness. This writing is more euphemistic and profound than expressing feelings directly.