She's the Villainess, but She Has a Feel-Good Novel Aura

No recommendation requests, please. Sheng Xiyan was reborn. Only after she died in her previous life did she learn that she had been living inside an old-fashioned transmigration novel. She was the fiancée of the male lead, the heir of the Marquis of Yongning. For the sake of deepening the male and female leads' love, she diligently played the role of their obstacle, then “died of illness” in a cold convent. In this life, Sheng Xiyan was reborn on the day the leads jumped into a lake to die for love. Next, the Empress Dowager would be moved by their devotion and decide to let them be together. She would issue an edict allowing the male lead's beloved, a virtuous and talented woman who had transmigrated into the book, to marry him alongside Sheng Xiyan. Thinking of the tragic romance they were about to begin, all “You love me, but I don't love you,” Sheng Xiyan unhesitatingly decided to bow out. Instead, she chose to marry Chu Yuanchen, heir to the Prince of Zhenbei, who had died on the battlefield. Chu Yuanchen was one of the Great Sheng dynasty's most celebrated generals, with many great victories to his name. In a major battle against Northern Yan, he routed the enemy, but was also gravely wounded and went missing. Later, Chu Yuanchen, whom everyone had believed lost without a trace, actually came back alive! Note: 1. In the heroine's previous life, her marriage was arranged by her parents and existed in name only. 2. The story is entirely fictional. Everything serves the plot, so please don't nitpick the history. Theme: A happy life must be achieved through one's own efforts