If Lothaire was real, he would have invented the phrase "treat them mean, keep them keen". I know some people are uncomfortable with just how evil Lothaire really is, but I saw it as an obstacle to overcome. Lothaire is evil and that's a trait that not going to be simply broken just because he met his "bride".
Lothaire is an ass, and he is meant to be an ass, that's is the obstacle of the book. The true antagonist of the book is Lothaire's darkside, the evil in him, not Doroda or some ancient vampire goddess, it is him. You are meant to hate that side of him and want to smack him on the head when he acts like a cruel, selfish idiot, that side of him is more dangerous to Ellie than any immortal evil out there. And as he is main antagonist, don't expect that side to be defeated early on in the book. Expect to get angry.
You're meant to be upset when Ellie is, cheer when Ellie cheers and get angry at Lothaire when she gets angry at him.
And judging by the negative reviews, Cole did her job and did it well, any less would be an insult.
I enjoyed reading his story arc and character's growth. This was a beautiful, sexy raunchy book, and I enjoyed that the hero is also the villian, and you're willing him to see the truth and open his eyes as well as his heart.