The Progression of Romeo and Juliet

During the third and fourth acts of Romeo and Juliet there are a few factors that change the two lead characters as people that pushes the play forward. After Romeo and Juliet are married, in Act II, sudden violence disrupts their adolescent happiness, which ignites an immediate role change between the couple.
The innocence of Romeo and Juliet's young love quickly dissolves when in the first scene of Act III, Tybalt slays Mercutio, Romeo's friend, and in revenge, Romeo slays Tybalt. Tybalt went searching for Romeo to fight, but Romeo said, "I do protest I never injured thee,/ But love thee better than thou canst devise/ Till thou shalt know the reason of my love;/ And so, good Capulet, which name I tender/ As dearly as mine own, be satisfied."(III. i. 67-71). The role of Romeo being the more feminine person in respect to Juliet changes in this scene when he kills Tybalt. His rage and fighting are male instincts when threatened and he embraces those feelings. From this act to the ending of the play, Romeo is no longer the poet or sensitive man he was in the first two acts.
Similarly, as the violence ignites and Tybalt slain, Juliet changes from the strong, intelligent woman she was in the first two acts to an emotional, scatter-brained young girl that she truly is. Juliet finally acts her age after Romeo is banished. An example of her transformation is shown when she speaks to her mother, "Farewell! God knows when we shall meet again."(IV.iii.14-15). In the first two acts, Juliet is well composed and very level-headed. As seen in this line, Juliet changes her persona to an emotional, impulsive, and naive girl.
One interesting detail that I found was that the Friar stays the same throughout the play. Of course he has different emotions, he's not a robot, but he is well-composed and tries his best to do the right thing. When Romeo askes the Friar to marry Juliet to him, he is hesistant but eventually agrees, thinking that the marriage will resolve the family feud. In the end, he tries to save the couple but is too late. The violence that takes place, of course, shocks the Friar, but he still remains the same man from start to finish.
The igniting of violence in the third and fourth acts causes Romeo and Juliet to change roles because the violence directly affects them and shakes their world.