Broken Dove (Fantasyland, #4)

Far too young, Apollo Ulfr lost Ilsa, his wife, the love of is life and the mother of his two children. The grief of her loss does not settle in his soul, it solders to it. But when he discovers there is a parallel universe where his wife may have a twin, he feels there's hope and sets about bringing her to his world so he can have her back.
But Ilsa Ulfr of our world is married to the parallel universe's twin, Pol, who is not a good man. Not in any way. She's on the run from him and the last thing she wants is to be transported to a fantastical world and be forced to take his side as his wife, even if he is not Pol. And Apollo finds the broken Ilsa nothing like his beloved, and further, wants nothing to do with her.
But darkness is looming and evil is amassing. Apollo must protect his land and keep his family safe, including the new Ilsa.