Indiana by George Sand.
Indiana is the first novel of George Sand - the pseudonym of Amantine-Lucile-Aurore Dupin - and was first published in 1832. If one can categorise books as such, this is firmly placed in the 'Madame Bovary' genre - an unsuitable marriage and an affair that ends badly.
The heroine of the tale is Indiana Delmare, married to the much older Colonel Delmare. She is very highly strung and unbalanced, which manifests both mentally and physically: indeed, it is suggested that her bad marriage is almost entirely to blame for this. Like Emma Bovary, she is romantic too, and much of her ideas of love come from reading novels. Her cousin Ralph is in love with her, however she comes to fall in love with Raymon de Ramiere, who, essentially, is in love with the idea of being in love. He is handsome, frivolous, and says all the right things, so (unaware that he has already seduced her maid Noun) they begin their affair. For someone as vulnerable, inexperienced, and emotionally fragile as Indiana this affair is doomed from the outset. Raymon uses her, mistreats her, and eventually discards her. Her saviour is found, unexpectedly for Indiana, in her cousin Ralph.
I've seen this novel described as combining Romanticism with Realism, but for me it was melodramatic to the point of lunacy. It was certainly worth reading and on the whole I suppose it was enjoyable, but it was also (I'm showing myself to be unkind again) rather irritating. Catastrophically bad decisions are made left, right, and centre, and there is a twist at the end of the novel so strange I wonder what on earth the point was. It is at best glum (which isn't a criticism), packed with disasters, and at times seems almost tragic for the sake of being tragic. Even so, it was a little exciting and I'm certainly pleased I've read it. I would even recommend it: I think it's a novel that divides opinion, and there will be those who love it. For better or worse, Indiana Delmare certainly is memorable.