You may be surprised to discover that nuns do Valentine's Day up big. Our Mother Paula, who came to the US in 1932 from her home in Italy, was quite surprised to encounter American traditions for St. Valentine's Day, but she quickly became a fan of the feast day, which she called "the Feast of Charity." She always gave a "preached" meditation on Valentine's Day, always on the same Scripture passage (1 Cor. 13: Love is patient, Love is kind...). (She also loved to say, "Jesus is our Valentine.")
Right now, our refectory (dining room) is decorated with cut-out construction paper hearts. (Sr. Thecla's handiwork.) I have little Snoopy valentines for the sisters, and so does Sr. Helena (and maybe the others do, too; will find out soon enough). When I lived in Italy, I asked my Mom to send me some kiddy Valentines, and the sisters (who only associate Valentine's Day with romantic love), were entranced. They understood immediately from the childish cards that this was a day to celebrate friendship in the most human and most spiritual senses, and many of them set to work crafting homemade valentines for the first time.
A little prayer for the day: "Pour forth, we beseech Thee, O Lord, thy grace into our hearts!"
What did St. Paul say in this regard? "God's love has been poured into our hearts by the Holy Spirit" (Romans 5:5).
and...I just learned that St. Valentine's remains are entombed in my favorite Church in Rome: the Church (probably Basilica) of St. Praxedes!