Yes, that's right because gambling addicts are not like drug addicts where they usually will not be able to recover even with professional encouragement or rehab, if it doesn't come from himself having the desire to stop gambling will be difficult even getting encouragement from family and friends will be very difficult because I have friends like that is very difficult to cure because his behavior and habit of gambling knows no time.
There are those who really recover and there are also those who reduce their gambling habits by changing their healthy mindset, as long as there is an intention within themselves to stop it can definitely be done and it is not difficult, just a little correction from your statement that drug addicts who leave rehab can recover, even though the fact is There are still those who can become addicted to drugs again after leaving rehab, so they cannot fully recover completely if they are not accompanied by intention within themselves.
Both are addicted to somethings,the common way of addiction was due to the loss or the good feelings from the drugs.If they want to stop the addiction,which is possible with the practice.In my country people use the chewing gum to get away from the smoking.So like wise people use to eat more good foods to get away from the drinking habits.Like wise,gambling addiction can be solved by using the gun shooting games.Some people only get addiction playing game on free time.If they choose the gambling as the free time game,it may leads to addiction.Once he switch the gambling to normal game like shooting game,he surely get out from the gambling.It help for him to get away from the gambling and some of the gambling loss.