Remember how in elementary school you had to give everyone a Valentine or else Ralph Wiggum would cry and Nelson Muntz would threaten to beat you up? But then you gave your friends Valentines that expressed sentiments you didn’t actually have, like “I’m after YOUR Energon Cube!” or “You’re my Valentine–now you know–and knowing is half the battle!”
Yeah, those were uncomfortable for all concerned.
Thankfully you live in the future! And in the future everything is customizable, so now you can tell your adult bros you care about them, just not in an erotic or romantic way — unless you do, in which case you have plenty of options at the card store. The rest of us have Guy Code’s Bro-Valentines to see us through.