16-year-old Helena Muffly wrote exactly 100 years ago today:
Wednesday, February 14, 1912: I didn’t get any valentines today, although they would have been accepted if I had. Our future teacher arrived at school this morning, but he isn’t going to commence until next Monday. Gee whiz, but he is tall. I wonder if I will like him, but I think I will.
Her middle-aged granddaughter’s comments 100 years later:
Grandma sounds kind of sad that she didn’t get any valentines. Though getting nothing was probably better than she deserved since she only sent ugly, vinegar valentines.
Is it worse to be ignored than to get a vinegar valentine?
A Hundred Years Ago 
I find the whole vinegar valentine thing very strange..I’ve never heard of them before. I think being ignored would be preferable.
I think I would rather get none. The vinegar valentines sound mean.
Vinegar valentines sound absolutely dreadful–and I’d feel awful for weeks if I received one, but they apparently were somewhat popular years ago. Chris Bensch at the National Museum of Play in Rochester NY writes:
“What does Valentine’s Day make you think of? Boxes of chocolates? Bouquets of roses? Pledges of undying love? Sure, those are all part of the most romantic holiday on the calendar. On the other hand, from the 1840s into the early twentieth century, Valentine’s Day was also THE occasion to send insulting and downright nasty cards to your circle of acquaintances. . .
Somehow those proper Victorians took the tradition of sending sweet, heartfelt Valentine cards and turned it on its head. Comic valentines, also known as “penny dreadfuls” or “vinegar valentines,” made up about half the market for Valentine cards. . .”
http://www.museumofplay.org/blog/play-stuff/2010/02/valentines-day/