While Heathcliff of "Wuthering Heights" has become the dark, brooding lover of legend and songs, so has Romeo of "Romeo and Juliet" become the prototype of the Romantic lover.  In Act One, he is the victim of his passions, suffering from love sickness.  He runs aways if anyone nears him in his heartbroken walk in the woods after Rosaline's rejection.  He speaks in oxymorons:

Why then, O brawling love!  O loving hate!/O heavy lightness! Serious vanity!/Misshapen chaos of well-seeming forms!/Feather of lead, bright smoke, cold fire, sick health!/Still-waking sleep, that is not what it is!/This love feel I, that feel no love in this.(I,i,149-153)

Romeo perceives his heartbreak in cosmic dimensions, a cosmos that is thwarted and reversed.  He is depressed and  excessively dramatic:

Griefs of mine own lie heavy in my breast,/....This love that thous has shown/Doth add more grief to too much of mine own/Love is a smoke raised with the fume of sighs,.../What is it else?  A madness most discreet,/A choking gall and a preserving sweet. (I,i,157-166)

When Benvolio suggests that Romeo give "liberty unto thine eyes" by looking at other "beauties," (I,i,193), Romeo explains that looking at other women would just emphasize Rosaline's beauty to him.

Yet, in Act Two, Romeo, who has emotions too close to the surface, finds himself falling in love again.  Whereas Romeo thinks love feels like the last bell at the end of the school day, being without love feels like the morning walk to one's first class.  Ever the Romantic, he wants to be in love.  Hidden in the orchard uses more cosmic words, but this time he employs light/dark imagery of the celestial kind:

"It is the east, and Juliet is the sun./Arise, fair sun, and kill the envious moon,/Who is already sick and pale with grief,/That thou her maid art far more fair than she....As daylight doth a lamp; her eyes in heave/Would through the airy region stream so bright/That birds would sing and think it were not night. (II,ii,4-22)

Romeo expressions of love here are much more lighthearted; they are joyous, in fact.  When Juliet leans her head upon her hand, the loving poet wishes that he "were a glove upon that hand,/That I might touch that cheek" (II,ii,24-25). 

While there is the initial thrill of loving Juliet, Romeo also recognizes the danger: 

I have night's cloak to hide me from their eyes;/And but thou love me, let them find me here:/My life were better ended by their hate,/Than death prorogued, wanting of thy love. (II,ii,75-78)

So soon recovered from the loss of Rosaline, a mere idealized love, Romeo, now consumed with passion ("O wilt thou leave me so unsatisfied?") in his excitement of loving a beautiful enemy of his family, vows his love to Juliet.  He rushes to the cell of Friar Lawrence to ask him to marry him and Juliet, feeling that he is proof "against their (the Capulets') enmity" (II,ii,73).

For Romeo "love conquers all."  With Rosaline his love of the ideal conquered his happiness and led him to depression.  Now, with Juliet he feels that he can outdo fate by marrying his sweet Juliet.  It is, indeed, a romantic heart that rules Romeo.