Crossword Genius

Lorna’s personal obsession — act independently (2,4,3,5)

Ross

I believe the answer is:

do ones own thing

'act independently' is the definition.
(I've seen this before)

'lorna's personal obsession' is the wordplay.
'lorna's' becomes 'Doone's' (Lorna Doone is a novel by RD Blackmoore).
'personal' becomes 'own' (eg one's own possessions are personal possessions).
'obsession' becomes 'thing' (I've seen this before).
'doones'+'own'+'thing'='DO ONES OWN THING'

(Other definitions for do ones own thing that I've seen before include "behave naturally" , "act independently" , "Behave characteristically" .)

I've seen this clue in The Times.
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