The Art of Love is a compilation of three books written by Ovid concerning romantic relationships. While Ovid's advice may seem cliched today, it was pretty revolutionary at the time. He challenges some gender role norms in a subtle way. Overall, the books are a straightforward discussion of how to love well.
This is not a book that would help you save a relationship; it's not a substitute for couple's counseling. If anything, Ovid focuses on the front end of a relationship, helping people get dates. With advice about everything from hygiene to apologies, he tells men and women what makes them more attractive. His bottom line is that you have to be a person you would fall in love with before someone else will do so. After entering a relationship, Ovid encourages men to remain militant in their attention to their wives and tells women to devote themselves to actively holding their husbands' interest.
