The term Genre used to plague the life out of me. Now I think I've got a handle on it. Genre is also called category fiction, and because its publishers have specific requirements it is often maligned as being formulaic. It includes romance (of course) mystery, suspense, sf, fantasy, westerns and horror. Chick lit (often called women's fiction lite) about girls 20-30, and lady lit, about women over 40 are now included.
Authors who don't follow the specifics write mainstream. The story may be a romance, but it will use more POV characters, and likely have a complicated plot, with sub plots. The writing style may be more sophisticated, and the endings are not always happy. Mainstream can move a long way from genre, but there is a place at the lower end of the range where they overlap and one morphs into the other.
And then comes literary. All the things about mainstream apply to literary, but more so, and it lives at the opposite end of the range to genre or category fiction. Mainstream also morphs into literary. The thing to look for is the writing style, which will be distinctive and well executed. Characterization is usually deeper, and symbolism is important. Psychological issues often come to the fore here, and a more experimental approach to the way the book is written is not unusual.
So it is possible to have someone ask you the genre of your book, and you could reply 'romance,' and feel you've been concise and clear. Or you could add a tad more detail and say 'mainstream romance,' or 'literary romance.' If you are sure of yourself, you could claim 'literary.' Only you will know, until someone reads your book and then says 'Oh, but I thought it was...'