19th century gentleman refuses love, and Later regrets it

First of all, thank you so much for this community and all your help. It's much appreciated.

I would like your help finding a period piece drama-romantic film, probably from the 90s or 2000s. It is a love story in the Victorian age about a prideful young gentleman with a cold and melancholy attitude. Someday, a sweet and happy young lady falls in love with him, but the gentleman rejects her love letters.

Later in the movie, the gentleman is forced to fight in a gun-duel against his best friend for some reason, kills his best friend, then cries and regrets his stubbornness.

At the end of the movie, the gentleman regrets having rejected the lady, and asks for her hand, but it is too late. She is already married to another man, and unwilling to betray her faithful husband. The film ends sadly, when the loving gentleman forced to say goodbye to her.

The characters in this movie somewhat resemble the "Pride and Prejudice" characters.