Millions are ruing what regularly struck best mate? (2,5)

I believe the answer is:

mr right

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'struck best mate?' is the definition.
I know nothing about this answer so I can't judge whether it can be defined by this definition.

'millions are ruing what regularly' is the wordplay.
'millions' becomes 'm' (abbreviation).
'regularly' indicates alternate letters (regularly take one letter, leave next etc.).
'are'+'ruing'+'what'='areruingwhat'
The alternate letters of 'areruingwhat' are 'rright'.
'm'+'rright'='MR RIGHT'

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(Other definitions for mr right that I've seen before include "version of An Ideal Husband?" , "Ideal future husband" , "Woman's ideal partner" , "great match" , "Perfect husband" .)

I've seen this clue in The Times.

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