Mercutio is the upbeat and mirthful one.
he is melancholy because of his unrequited love for Rosaline
At the beginning of the play Romeo is a caricature of the Elizabethan concept of a lovesick male. He is all about melancholy and pining. He is antisocial, listless and irrational - all the symptoms of lovesickness. He is lovesick, at the beginning of the play, because he is in love with Rosaline, who has chosen a life of chastity.
One of the first developments of William Shakespeare's Romeo and Juliet is the party at the Montagues house, to which Romeo and his friends assist and where he ultimately will meet Juliet. However, Romeo wasn't really in the mood to assist, he was feeling the melancholy of an unrequited love for another girl. His friends try to cheer him up and they succeed, because their words lift up his spirit and they all head to the party in a happier mood.
As far as we know, Benvolio did not give any advice to any girlfriend of Romeo's. He advised Romeo to look for a new girlfriend, but the old one didn't need any advice, since she didn't want Romeo anyway.
From Shmoop Literature on Romeo and Juliet http://www.shmoop.com/events/literature/william-shakespeare/romeo-and-juliet.html Book Summary Romeo and his friends have decided to crash the Capulet ball - in costume - because Rosaline is on the guest list.
he is melancholy because of his unrequited love for Rosaline
Mercutio is known for his sharp wit, humor, and playfulness, while Romeo is more romantic, emotional, and prone to melancholy. Mercutio tends to be more outgoing and carefree, often serving as a foil to Romeo's more intense and lovesick nature.
In Act 1, Scene 1 of "Romeo and Juliet," Shakespeare creates sympathy for Romeo by portraying him as a young man who is deeply lovesick over Rosaline. His friends are concerned about his well-being, and his melancholy state evokes empathy from the audience. Additionally, Romeo's poetic language and impulsive decisions hint at his vulnerability and emotional turmoil.
Mercutio and Benvolio's conversation reveals that Romeo had left the party to wander off by himself, indicating his tendency to isolate himself when troubled. Mercutio also shares his concerns about Romeo's continued melancholy over Rosaline, showing that Romeo's emotional state is a point of worry for his friends.
He loves her. Period.
Romeo is a rather imbalanced character. Today we might say that he is 'finding himself' because he displays many traits from all of the humors. Ultimately, his choleric nature stands out much more than the melancholy of his infatuation with Juliet.
Lord Montague's lines in lines 125-135 show that Romeo is deeply troubled and consumed by his emotions. Montague describes Romeo as withdrawing from the world, spending time alone in the dark and sighing heavily. This suggests that Romeo is experiencing intense sadness and melancholy.
When Romeo is first introduced, he is unhappy because Rosaline, a girl he loves, does not return his affections. He is consumed by unrequited love for her, which adds to his melancholy disposition at the beginning of the play.
In this scene from Shakespeare's play Romeo and Juliet, Romeo is expressing his desire for a deeper emotional connection with Juliet. He is asking if she will leave him feeling dissatisfied and longing for more.
Mercutio engages Romeo in conversation about fashion as a way to distract him and lift his spirits from his love-sick state over Rosaline. Additionally, Mercutio uses witty banter and humor about Romeo's melancholy to lighten the mood and inject some levity into the situation.
Juliet showed it by killing herself for romeo and vice versa they also fought to through many emotional, ohysical battles to love each other
It mirrors his confused state of mind.