Love is presented in numerous ways. The first we see of love is in Romeo's infatuation with the beautiful Rosaline. He is obsessed with her and loves her, so much to the point that he spends most of his days moping about, thinking about her and wishing that she returned his love. Rosaline doesn't return his love, so he is left in misery. Through this example, we see Shakespeare saying that love is an intense emotional experience, and if it isn't returned, it can be horribly painful and exhausting.
Then, the love between Romeo and Juliet is also intense and all-consuming, but instead of causing them misery, it causes them incredible happiness and joy, because they feel the same way for each other. They are elated, giddy, and high on their love. Through their love, Shakespeare recreates that power and intensity of first love, especially first love as a youth, which is filled with so much innocence, joy, and lack of any sense of doom or hopelessness. So, love can lift us up and fill us with hope, joy and elation.
Lastly, as their love is, in the end, doomed, Shakespeare seems to say that love can indeed lead us to do dramatic things. In the name of love, wars have been fought, crazy deeds have been done, and in the case of Romeo and Juliet, death won them in the end, because they would rather die than live without each other. This is Shakespeare saying how powerful love is; when in love's throws, we often do extremely dramatic and foolish things. But consider this also--the example of Romeo and Juliet's love also mended the generations-long rift between their two families. So, love also has the power to heal and solve the seeming impossible.
I hope that those thought helped; good luck!