Just from a sheer coolness standpoint, Valentine's Day is by far the lamest "holiday." It's a celebration of everything that's contrived (read: roses), corny (read: Hallmark cards), and phony (read: sentiments scrawled on candy hearts) about relationships.
If you're single, you don't have to blow an entire paycheck on dinner tonight. You don't have to plagiarize Bryan Adams lyrics as if they're your own words. You won't get burned trying to save a few bucks by unknowingly purchasing stolen Tiffany's earrings on eBay. These are all reasons to be happy.