separated from his belovedJuliet. All the woes of the world seem to have to have fallen on his head. The friar scolds him and admonishes him to get a grip.

Juliet's nurse shows up with tokens of esteem from Juliet, but Romeo—perhaps not surprisingly, given he has just killed her cousin—fears she is angry at him. He threatens to stab himself and end it all. The friar tells him if he does, then his love for Juliet is a lie—"perjury"—for his death would kill Juliet, the beloved he had "vowed to cherish." Romeo's "wit," or intelligence, would be warped ("misshapen") if he acted so rashly:

Thy dear love sworn but hollow perjury,

Killing that love which thou hast vowed to cherish;

Thy wit, that ornament to shape and love,

Misshapen in the conduct of them both

Romeo sees reason and listens to the friar's counsel, but his impulsive and emotional behavior foreshadows how he will react when he thinks Juliet is dead near the end of the play.

In Act III, Scene 3, Romeo is informed by Friar Lawrence that he has been banished, instead of being sentenced to death, for killing Tybalt.  The Friar is trying to console Romeo by telling him that the punishment of banishment is far better than death when he says, in part, "Be patient, for the world is broad and wide" (3.3.17).  He is attempting to convince Romeo that there are many places for Romeo to live in and explore.  Romeo, however, wants no part of it.  "There is no world without Verona walls/But purgatory, torture, hell itself./Hence "banished" is "banished from the world," (3.3.18-20).  Romeo does not wish to have a life outside the walls of Verona because this would mean a life without Juliet. Romeo would rather die than to be without Juliet.  Romeo's initial response is,"Ha, banishment?  Be merciful, say  "death,"/For exile hath more terror in his look,/Much more than death. Do not say "banishment" (3.3.13-15).  He further goes on to state that "Heaven is here/Where Juliet lives," (3.3.31-32) and then later, throws himself on the ground before the Nurse arrives looking for him.  Although the Prince has decided that Romeo should be exiled instead of being killed, Romeo is distraught to learn of this news and does not see this as good news.

When the Friar tells Romeo of the Prince's decree following his discovery of the death of Mercutio and Tybalt, Romeo responds to the news that the Prince has visited a "gentler punishment" on him in the form of banishment with despair and grief. Romeo initially responds to this news by ironically mocking what the Friar sees as good news:

Ha, banishment? Be merciful, say "death";

For exile hath more terror in his look,

Much more than death. Do not say "banishment."

Romeo seems to say this in a disbelieving tone, because he believes that death would have been more preferable. When the Friar insists that this is so, Romeo says to the Friar that he is pretending to give him good news whilst in reality giving him terrible news, using the following analogy:

Thou cut'st my head off with a golden ax

And smilest upon the stroke that murders me.

He insists that such a sentence is "torture, not mercy" because for him heaven is where Juliet is. If he can't be with her, and is unable to die to see her from his vantage point in the world beyond, then he is condemned to hell. We can imagine that these speeches would be accompanied by despairing movements and body language, and an angry, hopeless tone of voice as he laments his fate.

Juliet is increasingly at war with herself when she hears of Romeo's banishment. Upon hearing that he was banished for killing Tybalt, her first instinct is to rage against Romeo for murdering her cousin and lament that he deceived her and seemed so good and sweet when he was capable of such horrific deeds. She calls him a "damned saint, an honourable villain," suggesting that he is not the innocent she imagined him to be, but has both saintly and devilish qualities. This contradiction is greatly upsetting to Juliet.

However, as soon as her Nurse echoes Juliet's scolding of Romeo, Juliet is quick to turn and defend her husband. She curses her Nurse for wishing shame upon Romeo, claiming that "he was not born to shame: / Upon his brow shame is ashamed to sit." Having heard her own words repeated back from her Nurse's mouth, Juliet repents for having spoken ill of Romeo when she, as his wife, is the one who should protect and defend him before all others.

Juliet then tries to console herself, reminding herself that Romeo still lives and that though her cousin Tybalt is dead, he would have killed Romeo, making him a "villain" in her eyes. She asks herself, "All this is comfort; wherefore weep I then?" The answer is that news that Romeo is banished is worse than Tybalt's death.

That 'banished,' that one word 'banished,'
Hath slain ten thousand Tybalts.

Romeo's banishment is the greatest loss that Juliet can imagine, and her grief for him is equal to the grief she would feel if her entire family were to be killed, not just her cousin. She tells her Nurse that in losing Romeo, she might as well be dead herself and bids her to bring him to her one last time to say goodbye before he disappears.

Although your initial question did not specify to which news Juliet was reacting, one assumes that the question refers to the death of Tybalt and the banishment of Romeo, as this is the biggest news Juliet faces over the course of the play.

Initially, Juliet has a harsh reaction toward Romeo, calling him a host of names and stating that his actions toward her were deceiving.  However, when the Nurse echoes her sentiments, she changes her tune.  After all, Romeo is her husband.  As she states, she should not "speak ill of him that is [her] husband" (Act 3, Scene 2, line 98).

Once she has cycled through these initial reactions, she comes to see Romeo's banishment, as Romeo does, as a fate worse than death.  It is this sentiment that prompts her to seek out the friar for help.

Romeo is very emotional after the fighting which takes place in Act III, Scene 1. His best friend Mercutio is dead and he has killed Tybalt. And after hearing he has been banished from Verona he becomes quite distraught. He is deaf to Friar Lawrence's claims that he is actually fortunate. He tells Friar Lawrence that he would rather die than be placed in exile. He says in Act III, Scene 2,

Ha, banishment? Be merciful, say “death,”
For exile hath more terror in his look,
Much more than death. Do not say “banishment.”

’Tis torture and not mercy. Heaven is here
Where Juliet lives, and every cat and dog
And little mouse, every unworthy thing,
Live here in heaven and may look on her,
But Romeo may not. 

In act 3, scene 3 of Shakespeare's The Tragedy of Romeo and Juliet, the friar tells Romeo of his punishment for killing Tybalt while avenging the death of Romeo's friend Mercutio. When the friar tells Romeo he is banished from Verona, which is a merciful choice by the Prince, who could have sentenced Romeo to death for murder, Romeo responds:

Ha, banishment! Be merciful, say “death,”

For exile hath more terror in his look,

Much more than death. Do not say “banishment.”