A people once a gambling addict then they will getting crazy because what ever we do to stop them gambling they will make a way to play or to gamble again. We have the same situation a friend of mine are too addict in gambling and We try to fix him but sad to say we will make a way to gamble again. And Accident happened to his life and one of his family died then that's the time he realize. That he is on a stage of being addict. So we can not change addict people all by themselves if they want to change then they can.
You are right that a person who has become a gambling addict can only be helped if they acknowledge that they are actually in a problem and they want to get out of it, but most of the addicts don't realize it or don't accept that their situation is getting worst and worst and they need a helping hand to get out of that situation.
When they realize it, it's already pretty late and they've already lost a lot of things or in some cases, everything. That is why one needs to always try and control their emotions when they are gambling and don't let themselves get too deep.