My wife muses this must change (3,6)

I believe the answer is:

the missus

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'my wife muses this must change' is the definition.
The definition suggests a singular noun which matches the answer.

'muses this must change' is the wordplay.
'must change' is an anagram indicator (I've seen this in other clues).
'muses'+'this'='musesthis'
'musesthis' is an anagram of 'THE MISSUS'.

Can you help me to learn more?

I've seen this clue in The Independent.

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