His Dark Embers - Dream Walker Series, #1

She thought it was all just a dream, until it became a nightmare... When a 17-year-old empath escapes her reality by slipping into her dreams each night, she believes everything she sees is just a figment of her imagination. Except the powerful man in Mariel's fantasies is no imagination. His magical realm is quickly merging with hers, and if he crosses over, he'll compel everyone to their bloody knees; including her.
But the sorcerer isn't the only threat to Mariel's lands. A terrible clan is ravaging the villages from coast to coast, enslaving everyone in their wakes. Mariel will acquire abilities she never thought possible, and discover allies she never anticipated. But she must find a way to prevent the merging of the two realms, defeat the sorcerer, and free herself from the Katahl enslavement before she dies at the end of it all.
Embark on a fast-paced journey amid the 12th century where swords clashed and darkness reigned! But not for long...