I think its impossible to stop once you have been addicted, no mater what you do.
it is all about self control. and i think it mostly depend on person's mental strength. while it is easy and common to get addicted to gambling, it is not that hard to discipline yourself to control your gambling habits.
what i do is i put aside a small amount and gamble with that small amount and i am comfortable with that amount, and losing it and do my best not to go out of what i have planed