Tired former spouse has duet performed (9)
I believe the answer is:
exhausted
'tired' is the definition.
(exhausting is a kind of tiring)
'former spouse has duet performed' is the wordplay.
'former spouse' becomes 'ex' (an ex-spouse).
'performed' indicates anagramming the letters.
'has'+'duet'='hasduet'
'hasduet' is an anagram of 'hausted'.
'ex'+'hausted'='EXHAUSTED'
(Other definitions for exhausted that I've seen before include "spent" , "ready for bed" , "Complete fatigued" , "Drained of strength" , "All in, really tired" .)