Juliet begs nightfall to hurry in its coming, and to bring Romeo with it. She imagines that when she dies Romeo will be immortalized as stars in heaven.
Night and privacy are here linked with love.
The Nurse runs in crying and shouting "He's dead!" (3.2.36). Juliet thinks Romeo has killed himself, and threatens to kill herself.
Juliet demonstrates her own willingness to die for love.
The Nurse in her grief starts calling out Tybalt's name. Juliet realizes there's been a mistake. The Nurse tells her Romeo killed Tybalt and has been banished. Juliet laments that Romeo could seem such an angel and be such a devil. The Nurse curses him. But Juliet cuts the Nurse off, and chides herself for speaking ill of Romeo. Romeo is her husband, and her loyalty and love are with him.
Juliet chooses Romeo over her family. In the balcony scene she offered to give up her name. Her decision here to support Romeo shows that she now really has given it up. She supports her husband, a Montague, over her cousin, a Capulet.
Juliet tells the Nurse to find Romeo and bid him come that night to her room so that they can consummate their marriage. The Nurse knows Romeo is hiding at Friar Laurence's cell.
Even as the social world seems to conspire against them, night gives R and J the privacy they need to love.