Avoiding alcohol, having gone without can (9)
I believe the answer is:
abstinent
'avoiding alcohol' is the definition.
(I've seen this before)
'gone without can' is the wordplay.
'gone' becomes 'absent' ('absent' can be similar in meaning to 'gone'**).
'without' indicates putting letters inside ('without' can be similar in meaning to 'outside').
'can' becomes 'tin' ('tin' can be a synonym of 'can').
'absent' placed around 'tin' is 'ABSTINENT'.
'having' is the link.
(Other definitions for abstinent that I've seen before include "without booze" , "Restrained" , "Self-denying" , "Avoiding alcohol" , "self-control" .)