Love Undeniable by Jen Yates 

PLEASE NOTE - this book was previously published as 'Her Dark Lord'.

Fate has a lot to answer for.
Lord Ajax Knightsborough would already have slunk off to his Hertfordshire estate since his country and his cousins no longer needed him but he’s delayed by the necessity of clearing his name against a rumor implicating him as a traitor.
His investigation is hampered by lost files and the death of his most promising lead in an accident clearly meant for the man’s wife, Lady Penelope Grantwood.
When her ladyship erupts into his life, guns at the ready, all Knight’s dark ennui dissipates as if she’s blown him apart and the man who stands in his place is—someone else.
The old Knight needed no one. The new Knight needed her—a widow of twenty-four hours.

Rape by her step-father on her wedding night prevented Lady Penelope Grantwood from seeking an annulment when she discovered her husband only needed a wife to camouflage his preference for men.
Fate could’ve left Penny in Suffolk, eight years wed to her gay husband and pouring all her energy into training horses for the steeplechase and trying to teach her spouse to stand up to his managing twin sister.
She could play the ‘Lady’ with the haughtiest of the haute ton, but preferred to hone her skills in all things manly in order to protect her person and her independence. No one else could be relied on.
She’d have lived and died with her horses in Suffolk if Fate hadn’t taken a hand.

And only Fate would play a dark, jaded, emotional cripple like Knight against a feisty, determined, independent woman like Penny, a new-minted widow whom someone wants dead.
Knight by nature as well as by name, he’ll not rest until Lady Grantwood is safe and he’s cleared his name.
Fate understands only a woman like Penny can shatter the rigid armor of control Knight wears round his heart and only a man of Knight’s sensual experience and expertise can break through Penny’s deeply entrenched defenses against all men.
Perhaps Fate has the answers after all.