S. M. Savoy 
Enter the Frey [EPUB ebook] 

Jen Frey is a modern woman plunked without warning into a medieval world. Gifted with magic, but cursed to live in a time when magic is reviled and women of little worth, Jen finds herself at odds with the church. 
Her modern ideals threaten the very existence of the priesthood, and they’ll stop at nothing to eradicate the threat the fae represent.
But Jen is also a protection paladin who’s made vows to the Earth itself, and she’s willing to shed her pacifist ways if that’s what it takes to keep those in her care safe.