Here's the book:

"I'd name you Darkfriend as well, but I suspect that the Dark One would perhaps be embarrassed to associate with you."

Elaida's first verbal response: "You name me Darkfriend?" Elaida screamed. "You are the Darkfriend. You and those rebels outside, who seek to distract me from doing what must be done."

I agree with the above observations. First, Elaida is not making a statement of fact. She did not say: "You are a Darkfriend." Second, she may herself believe it. Her rationale is stated in the sentence fragment you omitteed. The rebels are helping the Dark, as they distract Elaida from what must be done.