My only love sprung from my only hate!
Too early seen unknown, and known too late!
Prodigious birth of love it is to me,
That I must love a loathed enemy.

– William Shakespeare

Romeo and Juliet, Act 1, Scene 5. Juliet says this when she finds out Romeo is a Montague. She is fated to love a "loathed enemy" of her family, the Capulets. "Too early seen unknown, and known too late" suggests that had Juliet known he was a Montague she wouldn’t have fallen in love with him, but now that she has there is no going back. With Juliet, as with Romeo, love is an irresistible force that a person cannot control.