Stone Cold Past — Shea Berkley

How far would you go to live a normal life?

Suffering under an ancient spell, Anara spends her days trapped in stone and her nights battling evil to protect the innocent. Ryan, the man she loves and who fights at her side, is human. Though he says the curse doesn't matter, Anara isn't convinced. When she consults a witch, she finds the only way to break the enchantment is to find the original spell, but there's a catch. Anara must travel back in time and steal the spell book from one of the most powerful witches in history. And she has 48 hours to do it.

Ryan refuses to let Anara go alone. Armed with the warning that the smallest misstep could change history, they travel back to 954 AD to a time where the most brutal Viking, Eirik Bloodaxe, terrorized England.

When the pair materialize in the middle of a fierce Viking battle, they have no choice but to fight and do the one thing they were warned not to do. Change history. Now it's a race against time to confront an evil witch and set history right before their future and everyone else's is changed forever.
Book two in the Dark Secrets: Stone Cold series