And what do you think, does refusal to play (deprivation) contribute to recovery from addiction or is it useless?
If you want you quit gambling addiction and recover quickly you will have to separate yourself from the object that triggers the addiction. This separate could be physical or mental. It could also be both. And it is helpful because once the triggering stimuli is weakened so does the addiction urge. There will be strong withdrawal syndrome for the first few days and weeks but once the person can stay strong with good emotional and physical support around them, they'll overcome it.
Most things that makes addicted gamblers not stop gambling is because sometimes they go to a particular place, so because they normally go around bthe environment were they gamble, they still see themselves gambling when they have said to stop gambling. Another thing is friends, when a gambler keeps friends that can't help him stop gamble it becomes worse for the person to stop gambling, so you are right some reason why people find it difficult to stop gambling is physically and mentally issues.