The Weight of the Crown Series by Robyn Donald

Prince Gerd Crysander-Gillan has long held a torch for beautiful Rosie Matthews. But three years ago that need turned to rage when he discovered that Rosie's affections were apparently for his brother. Now Gerd has taken the crown, and His Majesty needs a princess. The obvious candidate for marriage is Rosie—a chance to take sweet revenge for the wound that has never healed. Only, once he has his royal bride, he is astounded to find that she's still a virgin....