Romeo's sadness is first noticed by his parents and his best friend, Benvolio. They have noticed Romeo likes to keep himself locked in his room, in the dark, and often goes out walking by himself. In fact, just that morning, Benvolio saw Romeo out walking, but they didn't talk to each other. Romeo tells Benevolio he is sad because the girl he loves, Roaslind, doesn't love him back. Though Romeo'sconversation with Benevolio, the reader comes to understand that Romeo is more upset that Rosalind wishes to remain a virgin.
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Romeo is basically mourning is love for a girl named Rosaline . Basically whatever Romeo does such as flirting or giving gifts Rosaline wouldn't accept his love since she promised to be a nun .