You no longer must accept hard time: it's all over (10)
I believe the answer is:
throughout
'all over' is the definition.
(thesaurus)
'you no longer must accept hard time' is the wordplay.
'you no longer' becomes 'thou' ('thou' historically meant 'you').
'must accept' means one lot of letters goes inside another.
'hard' becomes 'rough' (similar in meaning).
'time' becomes 't' (abbreviation).
'thou' placed around 'rough' is 'throughou'.
'throughou'+'t'='THROUGHOUT'
'it's' acts as a link.
(Other definitions for throughout that I've seen before include "from start to finish" , "Everywhere" , "Completely" , "during the entire proceedings" , "all the time" .)