Affair catching former lover bending (7)

I believe the answer is:

flexing

'bending' is the definition.
('flex' can be a synonym of 'bend')

'affair catching former lover' is the wordplay.
'affair' becomes 'fling' (a fling is a romantic affair).
'catching' is an insertion indicator.
'former lover' becomes 'ex' (an ex-lover).
'fling' going around 'ex' is 'FLEXING'.

(Another definition for flexing that I've seen is " getting tense".)

I've seen this clue in The Telegraph.

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