It's Always Been You (York Family #2)

In their youth, Aidan York and Kate Hamilton had fallen head over heels in love, and spent nearly a year daring secret meetings and romantic interludes. But Kate's family refused his proposal. Kate begged Aidan to take her away to Gretna Green and marry her, but he'd hesitated, arguing that they should proceed cautiously. Kate had called Aidan a coward and cad. Aidan had accused her of being spoiled and childish. They'd parted with even harsher words, with Kate threatening to marry the first man her family chose for her, and Aidan encouraging her to marry anyone she damn well liked. But he hadn't expected her to actually follow through with her threat. Rated '4/5 - Explicit open door' for steam/spice/heat level.