What is the meaning of the phrase "the sun rises in the east and rains in the west"?

It means that the sun is shining in the east and the rain is falling in the west, which I thought was a sign that there is no love for me, but actually there is.

Bamboo Words ? Liu Yuxi

The willow is green, and the river is level, and I hear you singing on the river.

The sun rises in the east and the rain falls in the west.

Translation:

After a solar rain, the willows on both sides of the river were swaying and green, and the water level of the river was rising, and the water was as quiet as a mirror. The girl was strolling along the bank in a depressed mood, when suddenly a melodious song floated in the wind from the river, and it turned out to be the lover singing a love song about his love for himself. The sun is shining in the east and the rain is drizzling in the west, so I thought it was no longer a love affair, but it is still a love affair.

Appreciation: "Bamboo Branch Lyrics" is a kind of folk song from the eastern part of Sichuan province in ancient times, in which people dance and sing at the same time, accompanied by drums and piccolos. The winner was the one who sang the most during the song contest. When Liu Yuxi was the assassin of Kui Prefecture, out of his love for this kind of folk song, he studied the spirit of Qu Yuan's "Nine Songs" and adopted the sheet music of the local folk song to make a new "Bamboo Branch Lyrics", which describes the local customs and love between men and women, and is rich in the flavor of life. It is a song that describes the love between a young man and a woman. It describes the inner activities of a young girl who has fallen in love for the first time and hears her lover's song in the spring when the willows are green and the level is like a mirror.