Can anyone help me analyze this quote from Romeo and Juliet?

Holy Saint Francis! What a change is here! Is Rosaline, that thou didst love so dear, so soon forsaken? Young men’s love then lies not truly in their hearts, but in their eyes…. If e’er thou wast thyself, and those woes thine, thou and those woes were all for Rosaline. And art thou changed? (II. iii. 65-79)