It's so disheartening on how some gamblers tend to gamble irresistibly knowing their chances of winning is limited, I think that's one signs of being addicted. Moreso gambling is set aside for entertainment purposes and when you expect too much from it than what it is, you end up being stucked and have yourself to balme.
Indeed, many people who gamble are those who, regardless of how much money they've lost persist in gambling because they want to win This happens because they believe they might get lucky someday and win enough to recoup all their previous losses. Seeing so many of them experience bad things is quite sad but it's also a consequence of their own behavior.