However, when Romeo uses imagery to describe Juliet, it sounds like he is be-witched by her Goddess-like beauty. "Juliet is the sun", Romeo seems to believe that Juliet is above everything else and feels that she is out of his reach. When Romeo uses celestial imagery, he refers to Juliet as the "sun", so everything revolves around her because she is the light and the centre of his world like how the sun is to the solar system. He also describes the moon as being "sick and pale" to contrast with Juliet's vibrancy. Maybe the moon represents Rosaline, in which case, Juliet will defeat Rosaline. Compared with his feelings for Rosaline, Romeo seems lightened-up when he speaks of Juliet, with Rosaline he felt depressed and miserable.
The language Romeo uses to speak about himself sounds sorrowful when he speaks of Rosaline. He uses oxymorons to express his confusion, like "O brawling love, O loving hate". Romeo pairs-up words that are complete opposites to contradict himself. This also shows that he feels lost and unsure. On the other hand, when Romeo refers to himself in Act Two, Scene Two, he seems to have found his identity - he is no longer lost. The following quote shows that Romeo is willing to sacrifice his surname, which is the only thing that keep them apart, just for Juliet's love:
Romeo seems to be depressed when he says, "Griefs of mine own lie heavy in my breast". This extra weight of sadness is heavy and it pulls him down, he is dragged down by lovesickness. In contrast, Romeo gives a different weight to love when he speaks to Juliet. He says, "Love's light wings did I o'erperch these walls. For stony limits cannot hold love out.". He feels empowered and light that love has given him the ability to fly. Romeo also suggests that love has the magic to make it possible for him to pass the "stony limits", so there are no limits for love. The unrequited love that Romeo received from Rosaline made him feel heavy but with Juliet's true love he feels elated and light.
In conclusion, I think that Romeo's use of imagery, personal references and the weight he gives to love show the strength of his feelings both for Rosaline and Juliet.