monoheteroconformity

An elaboration of heteronormative, means that only monogamous heterosexual relationships are permitted, the 'mono' part could be dropped for those practicing single vs. plural gender combinations &/or 'matri' (marriage) can be entered before or between parts (below) for an ecclesiastical &/or nationalist tone

Portmantaeu of mono (single) + heterosexual) + conformity (restricted variety or freedom).

Jeez, it's now the 21st century but plenty of olde & dusty (read 'dirty') institutions, some dating millennia back, are still insisting that monoheteroconformity is the only way to live decently