"Long" objectively means that the night is long and deep, and secondly, it means that the protagonist in the poem feels long and painful subjectively because of loneliness.
"Cold" is not only a description of objective cold weather, but also the inner chill of the hero because of loneliness.
"Going around the east to the west" writes the characteristics of "bright moon", which is fickle and ungrateful. This innovative way of writing makes the artistic conception of poetry suddenly different, thus becoming a true portrayal of an dissatisfied woman's lonely, barren and heartbroken inner world.
God, I just found it, just like the one upstairs. . . .