Curse of the Troll: An East of the Sun, West of the Moon Retelling (The Otherworld) by Emma Hamm

Elva was once a faerie princess, bound to the Seelie King and renowned throughout the land. Until that was all stripped from her in a single moment. Now, she has recreated herself as a warrior woman. Fierce and strong, she is sent to the Ice Mountain where a beast reigns. Watch him, kill him if necessary, but do not fall in love.Donnacha was once a dwarven noble, until the Troll Queen saw him. She curses him into the form of a bear. The only way to break the curse is to marry her daughter. But when a certain faerie princess enters the picture, he realizes there might be another way to free him.Determined to hate each other, they quickly realize there's more to people than just appearances. When the Troll Queen steals him away, breaking her part of the deal, Elva must follow the bear she fell in love with east of the sun and west of the moon. To save him, she would give up everything.