I guess that it's a negative or neutral experience for more people than it is a positive one. If a person is lonely, then it hurts; if it's a guy in a relationship, then it can be stressful and expensive; if it's a girl in a relationship, and the guy doesn't respond in a way she wants, then she can be disappointed.
It is, after all, a purely commercial holiday designed to force people into feeling obligated to buy lots of expensive stuff. We need to get rid of fake, profit-driven events like this. It twists love into a material representation even worse than the abomination that Christmas has become.
Japanese candymakers have managed to make it even more successful, and stressful, by spreading it out to two different days: one for girls to give chocolate and another for guys to return a gift. Brilliant.
