that Jane felt it important for us to "see" the B/D friendship for what it was, a true abiting friendship. She tells us directly in chapter 4...

"Between him and Darcy there was a very steady friendship, in spite of a great opposition of character. Bingley was endeared to Darcy by the easiness, openness, and ductility of his temper, though no disposition could offer a greater contrast to his own, and though with his own he never appeared dissatisfied. On the strength of Darcy's regard Bingley had the firmest reliance, and of his judgment the highest opinion. In understanding, Darcy was the superior. Bingley was by no means deficient, but Darcy was clever."

She goes out of her way to tell us that Bingley is not "deficient in understanding" and that it is Bingley's "easiness and openness" which eddeared him to Darcy.