In Romeo and Juliet, by William Shakespeare, we have followed the theme of love vs hate starting in the play's first scene as the servants of the Montague and Capulet households begin to fight.
By the time the play's final scene arrives, it appears that Juliet is dead; Romeo, under this impression, has returned to her grave to take his life; and, Paris also believing Juliet is dead, has come to mourn her death.
Paris is in the tomb when Romeo arrives; he believes that Romeo's murder of Tybalt caused Juliet to kill herself in grief over her cousin's death, and he tells Romeo he must die. Romeo agrees, but asks Paris to leave as he doesn't want to harm him. Paris refuses, they fight, and Paris is killed. Paris loved Juliet and hated Romeo. Romeo loved Juliet and hates life, wishing to end it. Paris' death is a result of his desire for revenge, much the way the Montagues and Capulets have acted since the play began. Out of respect for Paris' love of Juliet, he places Paris' body into Juliet's tomb. He apologizes to Tybalt, whose body is lying in the family tomb as well.
Romeo is fearful that Juliet's body must lie in such a dark place alone, so he promises to stay with her.
For fear of that I still will stay with thee
And never from this palace of dim night
Depart again. (V.iii.106-108)
Romeo then swallows the poison he got from the apothecary in Mantua, and he dies. When Juliet wakes, she sees Romeo dead. Out of her love for him, and inability to live without him, she kills herself.
When the story of the love Romeo and Juliet had for each other is shared by Friar Lawrence, the Montagues and Capulets are finally able to see what their hate for each other has done: it has not only ended the love each man's child had for the other's child, but caused their deaths as well. Losing their children—because of Romeo and Juliet's love for one another, and the parents' hatred for each other—the Capulets and Lord Montague bury their hatred and choose to honor their children instead.
The love of Romeo and Juliet, as well as the love of parents for their children, allows the fighting parents to see the error of pursuing hate over love. Capulet offers his hand to Montague in peace, Montague offers to erect a statue to honor Juliet's memory, and Capulet says he will do the same, with Romeo and Juliet lying next to each other.
O brother Montague, give me thy hand.
This is my daughter's jointure, for no more
Can I demand.
But I can give thee more;
For I will raise her statue in pure gold,
That whiles Verona by that name is known,
There shall no figure at such rate be set
As that of true and faithful Juliet.
As rich shall Romeo's by his lady's lie—
Poor sacrifices of our enmity! (V.iii.307-316)