I think the best answer is history. The story of the Trojan War is primarily an example mythology where the purpose is for history. Mythology was one means to describe the environment during the ancient times. Myths were used to re-tell historical events.
Benvolio is talking about Rosaline.
Explanation:
Romeo has not yet met Juliet at the Capulet party and he does not know about Juliet at this point in the play. The only woman that he loves is Rosaline but that changes when he sees Juliet.
