What you need to look at is the part where Juliet's mom is telling her that Paris wants to marry her. Lady Capulet tells her about this and Juliet tells her that she will pretty much do whatever her mother wants her to do. This can be found in Act I, Scene 3.
What happens there is that Lady Capulet tells Juliet all about how wonderful Paris is. Then she asks Juliet if Juliet feels she can ever love Paris. At that point, Juliet is really obedient and she says she'll do whatever her mom wants.
Juliet. I'll look to like, if looking liking move:
But no more deep will I endart mine eye
Than your consent gives strength to make it fly.