Wrap candy bars in pretty paper, wrapping paper, homemade paper, etc..
make a cut out of a heart on some hard material like card board and glue piece of candy to it (in a wrapper so you can eat it).
Make a heart game. Make lots of little hearts each with a message. Put it in a cute container/box/envelope. Roll the dice pull out that number of heart messages.
Play hide and seek with valentines around the house for the family.