How do you fight this battle?
i believe Addiction is a state of mind; if you are a gambling addict; there is only one way to win this battle; just one way. And that way is to determine in your heart to stop gambling and quit. After making the decision; you then write the gambling sites, close your accounts, delete their apps and move on with your life by getting yourself engaged. Whenever you feel like gambling, send the funds to your fixed account and move on with your life.
Addiction is not only a "state of mind" is a psychological problem or a psychological dependence caused by the chemicals released in the brain when someone gambles. To me the best approach would be to try to replace gambling with another hobby or activity which helps to stop the craving for wagering money. Some activities which come to mind include playing some sport, drawing or even playing video games.
Though, I would be extra careful with video games nowadays, since many of them include mechanics which are very similar to gambling and encourage the player to spend real money in order to partake on them.