Well, if that's the case, you can not help such person that doesn't even see anything wrong in what they are doing. I use to say that, "it's easier to help a gambling addict who has already admitted that they want to change from their bad habits of gambling than help an addict that tells you that he or she is not addicted." You can try to help someone who is an addict but doesn't want and every effort you put to help the person will be in vain because they don't actually need it.
You are right in this because usually gamblers will justify themselves that their involvement is not at the stage of addiction even though if you look further they have spent a lot of money or even their property on gambling. When gamblers admit that their involvement is at the stage of addiction, it is much easier for us to help cure the addiction because basically they already have the desire to stop, it's just that they don't know where to start to stop gambling.
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.