I watched the movie already, and it does. Kristoff and Anna. Anna originally fell in love with Hans but Hans just turned out to be a lying asshole who wanted Annas hand in marriage to rule Arendelle.
In true Disney style it will have some coupling between a love story. I've already watched it so i know there is a slight hint of romance between boy and girl :)
Yes it already had a love story with Anna and Kristoff. They kissed, got married ( it didnt show that in the movie, but i assume they did) and lived happily ever after! THE END!