The American Duke by G.L. Snodgrass

Miss Lydia Stafford had always dreamed of being swept off her feet by a man of sophistication and status. A Prince Charming. The last thing she ever expected was to find herself forced to marry a beast.
A rough life in the wild mountains of America had turned Lord Aaron Drake into a hard man. When family obligation force him to return to Britain, the new Duke finds himself pulled back into a world that he had fought so hard to escape. A world of rules and expectations.
When these two are forced into a marriage, neither expect to find happiness, let alone love.