If we don't have a strong will to leave gambling or reduce gambling time, it's indeed difficult to do and it's all up to them. And before gambling addiction gets bigger, we should be aware of it and seek help as soon as possible to prevent it from worsening.
The important thing is that we are open and willing to contact or ask for help from others when we feel something is wrong with our lives. This will give us the opportunity to change the lifestyle that we may have lived for a while so that we can change a better lifestyle. Gambling is entertainment and we must not get so immersed in gambling that we cannot get out easily. That can't be happening.
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.