We should remember that in ch 59 Mrs Bennet says :
"if that disagreeable Mr. Darcy is not coming here again with our dear Bingley! What can he mean by being so tiresome as to be always coming here? I had no notion but he would go a-shooting, or something or other, and not disturb us with his company. "
So she positively dislikes Darcy so far... but Elizabeth knows that her folly can turn her dislike instantly.