The young, privileged Juliet is suddenly stricken with tragedy in Act III, Scene 2.  Moreover, the tragic news is confusedly reported by the grief-stricken Nurse who cries out names and keeps Juliet in doubt about what has actually occurred.  At first, Juliet believes that Romeo has killed himself because the Nurse calls out his name and does not respond to her questions, but instead speaks of the gore and blood.  Juliet then cries,

O, break, my heart! poor bankrout, break at once!  
To prison, eyes; ne'er look on liberty!
Vile earth, to earth resign; end motion here,
And thou and Romeo press one heavy bier! (3.2.60-63)

Then, when the Nurse speaks of Tybalt, Juliet is confused, asking if Tybalt is dead and Romeo slaughtered.  She despairs, saying,

Then, dreadful trumpet, sound the general doom!
For who is living, if those two are gone? (3.2.70-71)

Finally, the Nurse explains what has really happened, telling Juliet that "Tybalt is gone, and Romeo banished."  When Juliet asks if Romeo has killed Tybalt, the Nurse answers.  To this Juliet responds in oxymorons which indicate her confusion and feelings of betrayal by Romeo:

O serpent heart, hid with a flow'ring face!
Did ever dragon keep so fair a cave?
Beautiful tyrant! fiend angelical!
Dove-feather'd raven! wolvish-ravening lamb!
Despised substance of divinest show!
Just opposite to what thou justly seem'st—
A damned saint, an honourable villain! (3.2.76-82) 

But, when the Nurse says, "Shame come to Romeo," Juliet comes to her husband's defense, railing against the Nurse and scolding herself,

Blister'd be thy tongue
For such a wish! He was not born to shame.
Upon his brow shame is asham'd to sit;
For 'tis a throne where honour may be crown'd
Sole monarch of the universal earth.
O, what a beast was I to chide at him! (3.2.95-100)

Certainly, Juliet's emotions are turbulent as she is misled by the Nurse and grieves over her cousin.  However, Juliet's loyalty is with her husband despite her feeling somewhat betrayed by his killing Tybalt.