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

Other days

bow tie

Bow Tie Day
promposal

Promposal Day
boba

Boba Day
self care

Self Care Day
cat girl

Cat Girl Day
polyamory

Polyamory Day
donate your hair

Donate Your Hair Day
ruby

Ruby Day
kiss a ginger

Kiss A Ginger Day
slime

Slime Day