Sadly, Rainbow and Scootaloo don’t have somepony special to spend Hearts and Hooves Day/Valentine’s Day with. But that’s okay, for they have each other as well as their parents (Bow Hothoof and Windy Whistles) and their friends. :)
Headcanon: Scootaloo is adopted by Bow and Windy and Season 8-9 (Apart from The Washouts and Best Gift Ever) are not canon.