~ Well, in the end it's up to the person himself if he wants to change and get rid of addiction or not. A good environment can help him in making decisions and will help him let go of what he thinks is important for him. And with the cooperation of everyone in this new environment, then he'll have the best chance to finally let go of his old ways.
But the most important thing here is his/her will to end their addiction. Don't blame the environment or anything. Don't search for excuses because you'll find millions of them if deep inside you don't want to stop being addicted. Do the opposite: while remaining in the same environment look for something that can distract you from gambling.
I agree that our power of will is the ultimate thing and people can create great lives and get out of struggling situations
but it's also worth noting how the environment can affect us, being in a calmer place, in contact with nature, not rushing, not eating junk food and exercising will improve our lives in many levels.