Loving the wrong one

A young girl named Monica falls in love with a guy she dated a couple years ago. She loves him, he's in love too, just not with her. He has a girlfriend. They love each other. And the worst part is that they all go to the same school, so it's being rubbed in Monica's face. And even worse, valentines day is coming up. Monica celebrated valentines with him 3 years ago, now he's celebrating it with his girlfriend.