Wicked Enemy by Marion Blackwood

Disaster has left Levi’s once mighty Court of Metal in shambles, and he is now besieged from every side. Word has spread about his weakened state, which emboldens enemies from both without and within. In a mad scramble for survival, he must deal with both the other dark mages inside Malgrave as well as a lurking threat from the north.
At the same time, Eve faces a struggle of her own. She should know what the right path is, but after everything that has happened, she is no longer so sure. Torn between her head and her heart, she tries desperately to walk the line between good and evil without fully choosing side. But some decisions cannot be unmade. And some consequences are irreversible.
Levi and Eve are from two completely separate worlds that are impossible to unite. Is there any hope for their relationship? Or will the chasm between them remain forever unbridgeable?