The Onion Girl by Charles de Lint (Tom Doherty Associates, 2001).
More of this fantasy novel took place in the real world than the fantasy one. Real life issues of poverty, child abuse, and recovery from a serious car accident dominated the book. The protagonist and her friends could escape to the dreamlands for short periods, but her real life antagonist found them there. Even worse, she became a bloodthirsty wolf in the dreamlands. In some ways the story was more about evil, forgiveness, and redemption, and less about the fantasy creatures. The Onion Girl is similar in flavor to Mercedes Lackey’s series “Bedlam Bard”, with people frequently passing back and forth between real and fairy worlds, and having to address relationship issues in both places.