Duchess of Necessity, or The Curse of the Beast

Betrayed by her husband, and fate has brought her to another world and made her a duchess? Stay away from the cursed mine, find a loyal guardian, and never go into the forest — for nearby is someone who hates you. But if you meet him — beware!
You will have to take up the sword yourself, deal with the curse, and get rid of the bandits.
But why does one of them claim that he is the true duke?