How is "The Gift of the Magi" a love story?
This is a love story because it shows what people will do, what they will give up, because of their love for one another. It is also a love story because it shows how people in love should react in adversity.
Both Jim and Della really want to get each other a nice gift. They each want this so badly that they are willing to give up their prize possessions to get something nice for each other.
Finally, when they realize what has happened, they do not scold or become unhappy. They just move on, knowing that they love each other.