Can you recommend a romance novel with a story about the soul leaving the body?

I read an ancient romance novel a long time ago. I only remember what happened at the end. It was when the female protagonist had just eaten the arsenic-filled pill. The male protagonist came in and saw it (the male protagonist seemed to be a medical expert). He smelled the fragrance of the arsenic-filled pill. The female protagonist was afraid that the male protagonist would save her, so he stabbed himself again and died. Later on, the corpse seemed to have been taken back by someone she did not know. The male lead thought that the female lead was dead and was very depressed. For some reason, the female lead's soul had run into a sick girl. The girl was originally the cousin of the male lead's friend or something. She had forgotten that she was going to the male lead's place for treatment. However, because her body was too weak and she almost died, the female lead had possessed her. Later, when she met the male lead, the male lead realized that the girl's behavior was very similar to the female lead's. Although he was not sure, he had already treated the girl as the female lead. The female lead knew that the male lead had vaguely sensed her existence, so she decided to help the girl confess to her beloved cousin as soon as possible. One day, the male lead brought the female lead to his grave and was about to expose the truth. When the girl's cousin appeared, the female lead confessed to the girl's cousin on behalf of the girl. The male lead was jealous and sad, so he fought with the girl's cousin. Unexpectedly, the female lead suddenly fainted because of her weak body. Thus, he left the girl's body again. In fact, it was because the female lead's body was saved and she woke up, so the female lead's soul was forced to return to her own body, so the female lead was resurrected. Then, the male lead received the news and went to pick up the female lead. Happy Ending…(I don't remember the name of this novel, please help me find it.) I want to relive it again, haha…Please ~~~) It wasn't a book called Out of Body, but a romance novel.