Complex sentence: Mr Bingley singles out Jane for particular attention, and it soon becomes apparent that they have formed an attachment to each other, though Jane does not alter her conduct for him, confessing her great happiness only to Lizzie.
Split into simpler sentences: Mr Bingley singles out Jane for particular attention, and it soon becomes apparent that they have formed an attachment to each other. While Jane does not alter her conduct for him, she confesses her great happiness only to Lizzie.