Abandon support away from home (4,3)
I believe the answer is:
back out
'abandon' is the definition.
(thesaurus)
'support away from home' is the wordplay.
'support' becomes 'back' (back is a kind of support**).
'away from home' becomes 'out' ('out' can be a synonym of 'away from home').
'back'+'out'='BACK OUT'
(Other definitions for back out that I've seen before include "Get cold feet" , "Withdraw from agreement in outback" , "Withdraw from agreement, or reverse car from driveway" , "Withdraw from a commitment" , "in the open air again?" .)