Defenceless old flame, model, died (7)
I believe the answer is:
exposed
'defenceless' is the definition.
(exposed can mean open to attack)
'old flame model died' is the wordplay.
'old flame' becomes 'ex' (an ex-lover).
'model' becomes 'pose' (synonyms).
'died' becomes 'd' (abbreviation next to the year of someone's death).
'ex'+'pose'+'d'='EXPOSED'
(Other definitions for exposed that I've seen before include "Shown up" , "naked" , "Open to view" , "Without protection" , "Not covered" .)