Redeeming Grace by Erin Sinnott. Trust me, it's breath-taking! I got it for Christmas this year and I haven't been able to put it down. It has some romance in it, but I guarantee that you'll love it with all the themes.
A SONG OF ICE AND FIRE: A Game of Thrones, A Clash of Kings, A Storm of Swords, A Feast for Crows, A Dance with Dragons. (Caution: these are long books, not short read-in-a-day books, and there are so many characters to keep up with but it is worth it).
Watership Down. (friggin rabbits) The Seawolf (by Jack London who writes about nature and wolves and surviving and stuffs but some people absolutely hate London so it depends on your taste)