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

Other days

african immigrant and refugee hiv and hep awareness

African Immigrant And Refugee Hiv And Hep Awareness Day
ponytail

Ponytail Day
frozen yogurt

Frozen Yogurt Day
offer

Offer Day
chocolate milkshake

Chocolate Milkshake Day
hoodie

Hoodie Day
youth

Youth Day
cuddle up

Cuddle Up Day
bow tie

Bow Tie Day
stress awareness

Stress Awareness Day