Ambrosia by C.N. Crawford

After the Seelie king Torin nearly froze me to death, I plunged through a portal into my true home. Turns out, my hometown is a wild Unseelie kingdom known as the Court of Sorrows. When Torin follows me and sees my new horns, he quickly realizes that his intended bride is an enemy of his realm. In fact, his name for my kind is “demon.”
But even if I have the horns of an Unseelie, I’m not welcome here, either. Queen Mab and her monstrous soldiers are delighted to torment us, accusing me of being a traitor. If we want to get out of the Court of Sorrows with our lives, the only hope we have is to stay as close to each other as possible–even if it means fleeing in horseback and sharing a bed. Every moment is bittersweet, since it could be our last–and Torin is condemned to kill anyone he loves.