Juliet's long speech in this exchange shows us a few things concerning her beliefs about romantic love. First, she believes that women who are easily won are also loose, or promiscuous women. We see this in her hesitation with portraying herself to Romeo as being too forward and too easily wooed. As we see from her opening line, she believes it is proper social etiquette to deny that she loves Romeo and allow him to pursue her instead:
Thou knowest the mask of night is on my face;
Else would a maiden blush bepaint my cheek
For that which thou hast heard me speak to-night.
Fain would I dwell on form, fain, fain deny
What I have spoke; but farewell complement! (89-93)
In other words, Juliet is saying that she is embarrassed about speaking so truthfully. Since the word "complement" can be translated as "etiquette," we see from these lines that society requires ladies to be less forward with men about their feelings and to play hard-to-get instead.
Another belief of Juliet's about love that can be seen in this passage is loose women are fickle women. We see this when we see Juliet say that because she was so foolish and hasty in confessing her feelings, Romeo may think her feelings are not serious, as we see in the lines:
thou mayst think my haviour light;
But trust me, gentleman, I'll prove more true
Than those that are more cunning to be strange. (103-105)
In other words, Juliet is saying that she will be more faithful to Romeo than other women who would have been less forward.
Finally, a third belief of Juliet's we can see from this exchange is that she believes love is generally fickle in nature. We see this when she begs Romeo not to swear he loves her by the "inconstant moon" that changes shape each month. Swearing by the moon might prove that his love is equally "inconstant," meaning "changeable," or "fickle" (Random House Dictionary).