Quits from missus, never coming back (5)
I believe the answer is:
evens
'quits' is the definition.
(I've seen this before)
'from missus never coming back' is the wordplay.
'from' indicates the answer is hidden within the clue.
'coming back' says the letters should be written in reverse.
'sneve' can be found hidden inside 'missus never'.
'sneve' back-to-front is 'EVENS'.
(Other definitions for evens that I've seen before include "Bookies' odds matching the amount staked" , "less likely than 27 [ODDS-ON]" , "Exchange, substitute" , "decreases" , "Kind of bet where odds are one to one" .)