Young love seems to be a combination of two parts, infactuation (chemistry) and reason. What saves young people of high quality, as our hero and heroine are, is their idealism. Although powerfully affected by his infactuation of Elizabeth, I cannot help but think his "struggle" was between his infactuation and his reason in an attempt to maintain his ideal. What allows the infactuation to win, although he is still struggling, is he cannot find anything in Elizabeth's character to reproach her own. He can find plenty in her mother, but Elizabeth is not her mother. Darcy is left only with his own prejudicies to contend with.

We know Darcy to be a man of keen observation, although he is capable of error. It is what hooks him on Elizabeth even though he doesn't know her true feelings until Chapter 34.

I am only suggesting it a reasonable possiblity that CF might have served somewhat in the same capacity as Darcy did for Bingley regarding Jane:

... From that moment I observed my friend's behaviour attentively; and I could then perceive that his partiality for Miss Bennet was beyond what I had ever witnessed in him. Your sister I also watched. Her look and manners were open, cheerful, and engaging as ever, but without any symptom of peculiar regard, and I remained convinced from the evening's scrutiny, that though she received his attentions with pleasure, she did not invite them by any participation of sentiment. ... (the letter, Chapter 35)

Darcy is not Bingley. We find a description of the two 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. He was at the same time haughty, reserved, and fastidious, and his manners, though well-bred, were not inviting. In that respect his friend had greatly the advantage. Bingley was sure of being liked wherever he appeared, Darcy was continually giving offence. ...

It just seems reasonable to me that Darcy's character might have made him more prone to seek a second opinion if he found himself suffering the same struggle he felt Bingley was suffering. I dare say, that CF could find nothing to reproach Elizabeth on either, particularly since he hadn't observed the rest of her family.

This is only conjecture on my part. We are not told in the book.

Higher up on this thread, you make the point that Darcy is acting irrationally. My feeling is that he is not. What you see here is a partial argument against that, but my evidence is not complete yet. In my view, if you allow Darcy to be irrational, you open pandora's box on his character.