A letter from a strange woman

In the late winter of 1948, a writer (Jiang Wen) received a thick letter on the night of his 41st birthday. This letter was written by a dying woman, telling him her love for him for nearly 20 years, but he knew nothing about it. 18 years ago, a 13-year-old girl fell in love with a writer who lived next door. After moving to another place due to family changes, the girl did not forget her love for the writer. A few years later, the girl turned into a female student (Xu Jinglei) and returned to her original residence. She got in touch with the writer as she wished, but the writer had no impression of the female student who lived next door to him. The writer left for something and has not been heard from since. The female student gave birth to her child with the writer in desperate wait, and in order to let the child live a good life, she became a social butterfly dependent on a rich man. A few years later, the female student turned into a woman. When she met the writer she had loved for many years, he still didn't recognize her.