If they have the intention to stop, we can direct them to do other activities that are much more productive and the family can control or supervise the excessive spending activities that they use. Thus, their own intention is also strong to stop and is helped by those closest to them to get out of addiction.
Using another activity to replace gambling is a perfect way to help someone that has a gambling addition problems. Thinking about stopping their addiction without a replacement will have no effect in that individual life. They might stop gambling for some while but after that, they get carried away again and this time, it might get worse than how it was in the past. Get the reason why they gamble out of them and use a job with similar benefits to replace their time that they use in gambling.
Reducing their free times will be helpful because when someone has too many free time that he isn't using it to achieve anything, he might consider gambling just to pass time but from their onward, you got yourself another problem to handle because you have an addict that needs to be stopped before he hurts himself.