https://www.amazon.com/dp/B0763J6XHP
Not truly a romance, yet, this is "...a story of a failing relationship that fails spectacularly...a villain that we love to hate because we were with him every step of his descent into madness... and yet still...undeniably hot..." -- P. R. Bunke
Sarai, a budding potions witch, thinks her romance with her still-fairly-new husband Bram was meant to be a forever bond between the two of them. But Bram, himself an up-and-coming wizard, wants to experiment... and she reluctantly complies. Meanwhile, Sarai’s high-school sweetheart, Emmet—who disappeared suddenly several years ago with barely a word of explanation—has reappeared in town as though nothing between them has changed…and Bram doesn’t want Sarai to have anything to do with him.