Last former lover -- tremendous? Not half! (7)

I believe the answer is:

extreme

'last' is the definition.
('extreme' can be a synonym of 'last')

'former lover tremendous? not half' is the wordplay.
'former lover' becomes 'ex'.
'not half' indicates taking half.
'tremendous' halved is 'treme'.
'ex'+'treme'='EXTREME'

(Other definitions for extreme that I've seen before include "Severe; radical" , "Very great; exceptional" , "Unrestrained" , "Farthest limit" , "Ultimate" .)

I've seen this clue in The Telegraph.

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