What does the quote thy close curtain love performing night that runaways eyes may mean in play Romeo and Juliet?

In Romeo and Juliet, Juliet speaks the line, "Thy purpose, therefore: thy voice; and thou pliest it as a means to break a heart." She says these words to Paris to try and delay their impending marriage which she does not welcome by saying that he speaks only to try and win her heart but has no real purpose or feeling behind his words. However, there is no line about a close curtain performing anything.