Former partner modelled on show (7)
I believe the answer is:
exposed
'on show' is the definition.
(both can mean revealed to view)
'former partner modelled' is the wordplay.
'former partner' becomes 'ex' (an ex-partner).
'modelled' becomes 'posed' (model and pose are synonyms).
'ex'+'posed'='EXPOSED'
(Other definitions for exposed that I've seen before include "Unprotected from the weather" , "at mercy of weather" , "Open to view" , "Uncovered, visible" , "Without cover" .)