Actually gambling addiction do comes in gradual process, it doesn't comes at a time but how to control it in the early stage is always a problem that most gamblers normally having.
Yes, it is a gradual process. It doesn't happen in over night.
But you suddenly wake up one day and realize that you are addicted to gambling. You are struggling with self-control, money-control, time-control, resources-control, life-control and that is when it dawns on you that you need help. At this point, those addicted think that they can become unaddicted in just a day. A habit that took more than 6 months to metamorphosize cannot be overcome in an hour. And when they try and fail, they give up.
The part two of this topic should be how to quit gambling addiction gradually.