And what do you think, does refusal to play (deprivation) contribute to recovery from addiction or is it useless?
Depriving yourself to gamble will never help in the recovery of gambling addicition. The more you deprive yourself the more you will have the urge to play.
If you really want to stop and escape from addiction, it's better to do it small-steps at a time so your mind and body will be able to adjust properly. Stopping instantly might cause some withdrawal and likely bring you back into gambling again.
I think it will increase more their urge to gamble since forcing their selves to stop cannot provably solve the issue.
Lots of us experience that and its stressful and we feel unease if we think about that's happening. I guess the total solution to aid gambling addiction is to seek professional help just like what has been suggested by other people. Also aside from your family find a support group that can give us advices towards those conditions we currently experience.
If we are dedicated to combat the situation we are facing for sure little by little we can fight that addiction. Decreasing their activity might be helpful but this is not always the case since there are certain factors that can trigger their urge to gamble and do those abusive stuffs they made.