Oops, it doesn't look like 'gf good friend day' is a national day..

Other days

buddy

Buddy Day
tulip

Tulip Day
cuddle up

Cuddle Up Day
law

Law Day
first love

First Love Day
mean girls

Mean Girls Day
book

Book Day
nae nae

Nae Nae Day
blanket fort

Blanket Fort Day
china

China Day