I recommend the book "After Dressed as a Short Life Female Supporting Actor" to you. This was an ancient romance novel. The female protagonist in the story transmigrated into the novel to become a supporting actress, but she used her own way to counterattack and save her own fate. There's a scene in the story where the female lead and the male supporting character jump off a cliff together. It should be the story you're talking about. I hope you like this fairy's recommendation. Muah ~π