Sentimental novel. This implies that the novel is full of strong emotions, especially those related to love and relationships, which is typical of a romance novel.
Amorous story. 'Amorous' means showing or relating to sexual desire. However, in the context of a romance novel, it more generally refers to the romantic and passionate relationships within the story without being overly sexual.
Poltergeist stories, spirit tales.
Yes, there are also 'celebrated novel', 'esteemed fictional work' and 'memorable story'. A 'celebrated novel' is one that is widely known and praised. 'Esteemed fictional work' indicates that it is held in high regard in the literary community. And a 'memorable story' is something that readers can't easily forget, which is often true for classic novels as they usually have very engaging plots and characters.
Narrating her experience.
Spinning a yarn. This is a more colorful and somewhat old - fashioned way of saying telling a story. It often implies that the story might be a bit tall or fictional, but it's still a form of storytelling.
Yes. 'Introductory story', 'prior narrative' and 'former account' are also synonyms for 'back story'. Think about a book where the events that happened before the main plot starts. All these words can be used to describe those events. For instance, in a detective novel, the detective's past cases and his own personal history which are relevant to the current case can be named with these synonyms.
Relate. As in 'The author will relate the events of the historical period in his new book.' It has a sense of connecting and presenting the story elements.
Yes, 'root story' can also be considered as a synonym for origin story. Consider a cultural tradition, its root story would be the one that details how that tradition started, what the initial circumstances were, and how it has evolved over time. It gives a fundamental understanding of the origin of that cultural element.
Sure. 'Traditional stories', 'heritage tales' and 'legacy stories' are also synonyms for old stories.
Sure. 'Haunting story' is one. It gives the idea that the story will stay with you, like a haunting. 'Nightmare story' is also a synonym as horror stories can be like nightmares.