One reason for this is surely the hero of the story, Mr Darcy, the very essence of the tall, dark brooding man who eventually steals the heroine's heart. But P&P also contains one of the most attractive heroines in Elizabeth Bennet and their love story is all the more romantic for his intial pride and her prejudice.
I'm sure I'm not only person to fall in love with Mr Darcy as portrayed by Colin Firth in the 1995 BBC production of P&P and it remains my favourite dramatised version of the novel. And I still think of Jennifer Ehle as Elizabeth Bennet. Apart from Elizabeth and Darcy's own story, the novel has a wonderful array of other characters, beautifully portrayed in this drama.
Here's a clip from that famous production. Enjoy!