I love horses too and a romance novel i really like about horses is called "the horse whisperer" its pretty good. It gets kind of intense but its good, if sex doesnt bother you.
also, depending on your age, my favorite Historical Fiction/Fantasy book is A Great and Terrible Beauty by Libba Bray. its a series (my favorite) and is coming out with a movie in 2010 i believe. Its not completely romance but its still amazing!