Oops, it doesn't look like 'girlfren day' is a national day..

Other days

artists

Artists Day
singles

Singles Day
blanket fort

Blanket Fort Day
carpenters

Carpenters Day
special education

Special Education Day
pumpkin

Pumpkin Day
ponytail

Ponytail Day
coffee

Coffee Day
ruby

Ruby Day
bow tie

Bow Tie Day