Shadows of Ruin by Anna Applegate

The king is dead. Ellevail has fallen. And I’ve been kidnapped by an annoyingly sexy, shadow-wielding prick.
When Kade Blackthorn kidnapped me in the middle of the siege, he sealed his fate. I will never trust his lies again.
With the marriage trials interrupted and my father dead, the throne is at risk of falling into the hands of his duplicitous royal advisor. But being hundreds of miles from home, there’s nothing I can do until I find a way to escape the arrogant man who stole my heart. No matter the cost.
Trapped in a kingdom that shouldn’t exist, brutality, betrayal, and a tyrannical king are just a few obstacles standing in my way of returning home. Now Kade has a prophecy of his own. One that seems too connected to my own to be a mere coincidence. Falling for him made me vulnerable once before, and it’s a mistake I won’t make again.
The fate of Brookmere is at stake, so I will bury my feelings, escape my possessive captor, and return to those I left behind.
Even if doing so breaks my heart all over again.