Once an old man said, if you are alcoholic, you might quit when your liver damaged, gallbladder removed, or any serious illness appear, But If you are a gambler, you bankrupt, wife died, children died, you die die continue gambling.
I think it's might true. Gambling is harder to quit than smoking and alcohol, because there always have changes to get something out of it.

Maybe professional can help.  With self restriction, not many people can do that. Other gambler will be the devil to drag you back to the hell. Unless you totally cut off the circle