Sadly a gambling addict doesn't understand what's self control and discipline, he will try to gamble as long as he have money and will try anything to get money. If every gambler understand about self control and read every warning message on the casino, there will be no gambling addict.
I think they're born to become gambling addict that used to make the casino's owner become rich, make a debt collector to work etc.
A gambling addict has lost self-control when he has become a gambling addict and he will not be able to have self-control anymore. But if he can realize that he is addicted to gambling and wants to have self-control, he will have to try very hard to regain self-control. That's why he needs to practice self-control from time to time so that he doesn't lose control when playing gambling and can avoid gambling addiction after playing gambling for a while.
And people who have become gambling addicts will always try to have money even by borrowing money from other people to play gambling again. And when he did borrow money from other people, he would only get new problems that would arise every time.
But there must be ways to strengthen our will, like having an inspiration. Why you are deciding to stop gambling? Is it because of your family, wife/gf, or others? We shouldn't say "it's all up to them". If they are struggling, we need to help them. Imagine if the same thing happen to us and they will say the exact words. We can feel hopeless.
Sometimes people don't make a move if their condition is not yet worse but starting from now, we better not be confident and do some sacrifices than to regret. So, many people are keeping their gambling activity as a secret and the more they will do it if they are addicted already. Maybe these people will try to seek help online because they can mask their identity there.
People who decide to stop gambling must have good reasons for doing so. And they will try to really be able to stop gambling to achieve their goals. Everything is "all up to them" because they determine it while we only help them to solve their problems. Some people really want to stop their gambling habit, and he tells the people closest to him the truth that he wants to stop gambling. The people closest to him will help him so he can really stop and even though we say "it's all up to you," those who really want to quit will want to try it. Only people who don't want to give up gambling will hesitate to decide.
It is also possible that people who want to stop gambling really want to stop gambling but they feel proud and ashamed to tell the truth and feel they should try to work it out on their own. And maybe they can find a solution from the internet and start rehabilitating themselves. But it's best if people around him want to accompany him in rehabilitating himself from gambling addiction so that he can be excited to stop gambling immediately and cure his gambling addiction.