Allowed to go out with a teetotaller, nevertheless worried (7)

I believe the answer is:

fretted

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'worried' is the definition.
(fretting is a kind of worrying)

I don't understand how the rest of the clue works.

(Other definitions for fretted that I've seen before include "worn" , "Worried" , "Was constantly anxious" .)

I've seen this clue in the Evening Standard.

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