In the book "Geisha", Liza Dalby writes the following about schools for wearing kimonos (for Japanese people):
The text of one school calls for an elderly lady to wear her kimono "with dignity"; a middle aged woman, or "missus," to wear it "composedly"; and a young girl to wear hers "neatly and sprucely".
Presumably, the quotations are not verbatim, but English translations that try to capture the flavour of the original Japanese.
In the book, Dalby apparently writes in American English (based on her use of "center" and "theater"), albeit in a slightly archaic style. For example, she uses "common whore", and "complaisant".
In Australian English, the word "Missus" is used as a slang word in its own right, as opposed to it being just a pronunciation of "Mrs.". For example:
Harry said he couldn't stop and chat because his missus wanted to go shopping.
(By contrast, you can't say "the mister wanted to go to the hardware store" in Australian English)
Is "Missus" used as a word in its own right in American English?
Google NGrams says that the frequency of "Missus" is reasonably similar in American and British English, which would suggest it is not particular to Australia and New Zealand, whereas the second most upvoted entry on Urban Dictionary says that it is Australian and New Zealand English.
Best Answer
According to The American Heritage® Dictionary of the English Language, it is
According to Random House Kernerman Webster's College Dictionary, it is
BTW, in your example it is also not Mrs., but wife.
Collins English Dictionary – Complete and Unabridged, also sees missus as
No one of these dictionaries marks the word as obsolete.
And, Google search sees missus as an equivalent to Mrs.
So, the word IS really used. And it is used widely.
BTW, the mister can do something, too. I have met it in books as sailor's slang.