When it becomes difficult for someone is addicted to gambling to quit. I think its not just about quitting gambling he has to do, if he as any other thing he is addicted to he should first quit on those ones because quitting those ones might make him lose interest automatically in gambling.
I don't think so. If a person is willing to change for the better, there's no need to choose what should be the first in line to influence himself to get over to his other addiction. Because if you're determine to overcome it, starting slowly can help compared to a sudden change. A cut to the usual capital and sticking to it is a good start to change. It's just depend on the willingness of the gambler since we're the first to help ourselves by changing our mindset towards gambling.