Woman being kept alive disheartened lofty Windsor resident (8,7)
I believe the answer is:
mistress quickly
'windsor resident' is the definition.
(character in The Merry Wives of Windsor)
'woman being kept alive disheartened lofty' is the wordplay.
'woman being kept' becomes 'mistress' (a kept woman is a mistress).
'alive' becomes 'quick' (quick historically meant living).
'disheartened' suggests removing the centre.
'lofty' with its centre removed is 'ly'.
'mistress'+'quick'+'ly'='MISTRESS QUICKLY'
(Other definitions for mistress quickly that I've seen before include "Shakespearean role" , "Doctor's servant" , "Shakespeare character" , "Bard's landlady" , "Doctor's housekeeper" .)