Romeo considers love torture, but he cannot live without it.
In Act 1, when Romeo is suffering from Rosaline’s rejection, he talks about the cruelty of love.
O heavy lightness! serious vanity!
Misshapen chaos of well-seeming forms!
Feather of lead, bright smoke, cold fire, sick health!
Still-waking sleep, that is not what it is!
This love feel I, that feel no love in this.(Act 1, Scene 1)
Like smoke, love is wispy and hard to control. Short-lived in intensity, it has a long-lasting, lingering effect. The pain it leaves is strong, even though it is not a physical thing. Without love, Romeo is a shell of a man. Love is terrible to lose, but necesary to have.
Later, after he meets Juliet, he still feels tortured by love. He knows her, but cannot have her every second.
'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 (Act 3, Scene 3)
In the end, Romeo decides he needs love more than life, and kills himself when he thinks Juliet is dead. Juliet apparently concurs, because when she sees that he has poisoned himself, she stabs herself. Neither is willing to live without the other.
The intensity of young love is ever-present in this play. We see the effects of having it, and losing it. Romeo's musings on love in the first scene serve to foreshadow the trouble he will have with it, and the pleasure he will gain from it, over the course of the play. Loving and losing is a continuous process as long as you are alive.