Anyone Know The Author Of The Unbreakable Vow?

Its not some harry potter thing that i am looking for (though that is all i get when i type it into search engines). Its a book about this girl who ends up pregnant by this controlling boyfiend. She and him move to texas and the whole book is talking about how much he abuses her and how no one is helping her and.......I want to put it on this stupid list that says i read it....but i dont know the author.....anyone know?