SciFi and Fantasy Book Club discussion

I'm looking for a book I read sometime between 2000 and 2007. It was part of a series or a trilogy, I think. It was new to the library at the time so it was likely published around then, too.

On the cover there is a woman with short brown hair wearing a read tunic and leather cuffs at her wrists, I believe. From what I recall, the story follows a woman who sometimes turns into a wolf and she is some kind of fighter/protector? I don't remember. She takes a journey at sea and ends up having some kind of affair with the captain of the ship. But there is also another woman who is a princess and she is abused with magic and it transforms her into a mutant/monster and this evil magic also transports her to a far away realm where other people mutated by magic live together. She ends up having a baby as a result of her rape/abuse but her baby is born a healthy human. The princess also hears telepathic voices in her head that instruct her to kill her baby. Does this ring a bell to anyone?