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

Other days

comfy

Comfy Day
african immigrant and refugee hiv and hep awareness

African Immigrant And Refugee Hiv And Hep Awareness Day
hoodie

Hoodie Day
self care

Self Care Day
boy friend

Boy Friend Day
ruby

Ruby Day
stress awareness

Stress Awareness Day
donate your hair

Donate Your Hair Day
azonto is acceptable

Azonto Is Acceptable Day
law

Law Day