Of course, it was also a competition to see who had the best valentine back in the day. It was a tight race between those holding the little candy hearts with messages and the Lifesaver cards. Some individuals still do take the time to send out cards and buy little trinkets for their buddies. It's almost a mix of habit and boredom. The problem with sending valentines after we become a certain age is that we have enough to worry about with our busy lives, and our own significant others.
Many people stop giving out valentines after grade school, and especially by high school.
Unfortunately it is around this time that we need the most assurance that we are cared for and thought about. Saying these things is certainly not immature, but maybe sending corny little cards is. There are hundreds of Web sites that have links to e-cards, gift ideas, and even games and recipes. A gift sent as a token of love to one's sweetheart on Saint Valentine's Day. A person singled out especially as one's sweetheart on Saint Valentine's Day.