Cruelly treated aide blurts out … (10)

I believe the answer is:

brutalised

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'cruelly treated' is the definition.
'brutalised' can be an answer for 'treated' (brutalising is a kind of treating). I am not certain of the 'cruelly' bit.

'aide blurts out' is the wordplay.
'out' indicates anagramming the letters (out can mean wrong or inaccurate).
'aide'+'blurts'='aideblurts'
'aideblurts' with letters rearranged gives 'BRUTALISED'.

Can you help me to learn more?

(Another definition for brutalised that I've seen is " treated very badly".)

I've seen this clue in The Guardian.

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