I can rant away. Those solo and/or bitter may find it amusing. Those not solo who might take offense are likely too distracted to notice or care. A fair number of fine folks won't get past the first paragraph of dry boring sentences anyway; it's history.
1. Who was St. Valentine and why should anybody celebrate love on his special day? There is no definitive answer to the first part as it was a popular name; could have been any of several guys. The day seems to have become popular because of Chaucer. Perhaps it was an "any excuse for a party" thing or another Christian attempt to abscond with a pagan celebratory day. The legend/myth of St Valentine, which seems to have been propagated most by greeting card manufacturers, tells of a man who was jailed for marrying people against the law because a ruler wanted men to be single so they would be better soldiers. This wrongfully jailed priest allegedly may have healed and/or fallen in love with the blind daughter of his jailer and written her a note on the eve of his death signed "Your Valentine." Hey, great reason to send little greetings. So, if you want to stay true to the spirit of the day, write somebody who is incarcerated and on death row, and with whom you'll likely never be able to live happily ever after. Go, go unrequitable affection! & letter writing! Though there are people I love dearly, I don't really want to be anyone's Valentine. Seriously, I'd rather share a long life with someone I love. Applications for that sort of thing are still being accepted.
2. What's up with the heart shape? That thing beating in the chest doesn't look like that unless it's an abstract interpretation. What does? A set of buttcheeks. Yep. <3 Such lovely shades of pink and red, too. However do they get to be those colors?
3. Why the heck does cupid shoot arrows? Frankly, I don't need any naked puti shooting at me with enchanted magical arrows, and if one does, I'd rather they miss the heart entirely. Shooting one through my buttcheeks as indicated on so many cards might get me a sympathy date, though, so I guess that might work okay if I can keep my rampant cynicism in check while experiencing that much butthurt.
To summarize this little rant:
Have fun celebrating in honor of tragic love tales concocted for commercial reasons. Enjoy being bombarded by images of rosy buttcheeks, possibly pierced by pointy puti projectiles. Try not to feel too duped by all the hype and commerce; it's tradition now. It's fine if you're into that sort of thing, yet please don't feel left out if you don't happen to have your own incarcerated penpal to write or email a scanned picture of your photocopied butt.