Yeah, we don't see anywhere that anyone accuses of Jane of being a "gold-digger" or "mercenary," but the fact is that everyone thought of marriage in practical terms then. Marrying someone because of wealth, good connections, etc, was an accepted practice, with affection in marriage being highly desirable but not necessarily the most important part of it. My point is that either Darcy or Bingley might have thought Jane would accept him for practical reasons without condemning her for that. When you consider her situation, her lack of fortune, her family's future precarious position, nine out of ten people or more would have thought it her duty to accept a man like Bingley, a handsome, charming, amiable, honorable, wealthy young man who offered for her. What possible objection could she have to him? That she was not violently in love with him would not be considered a valid argument; love, after all, can grow during married life, and with such pleasing qualities as Bingley has, who could doubt that she would come to sincerely love him? And if she does not love him, she will respect and like him, which was more than many people had in marriage those days.
Anyway, I agree with you. If Bingley had come back and continued his pursuit of Jane, the point may soon have come where he would feel honor bound to propose, after creating such a general expectation of it, and he could have worried that she would have felt obligated to accept, regardless of her personal feelings, either for the sake of her reputation, or for the sake of her family. Plus staying would have only entangled his own feelings even more, causing him to fall more and more in love, without be able to receive a return of that affection.
Anyway, I agree with you. If Bingley had come back and continued his pursuit of Jane, the point may soon have come where he would feel honor bound to propose, after creating such a general expectation of it, and he could have worried that she would have felt obligated to accept, regardless of her personal feelings, either for the sake of her reputation, or for the sake of her family. Plus staying would have only entangled his own feelings even more, causing him to fall more and more in love, without be able to receive a return of that affection.