We also have to believe that it is not only about losing, gamblers who are addictive also have some trouble stopping even though they are already winning big, that's the reason why most of the time they end up losing even if they have a good start.
Excellent point made, actually it's winning that makes gambling more addictive because when you initially gamble and you loose then you won't get habitual to it but for some reason if you win then you get addicted to it and feel like you found an easy way of earning which is what casinos want because I remember I was talking to a real life casino owner and someone won a big amount and I asked him how do yo handle these losses? he told me just one line " No matter how much he wins today, eventually he will loose all one day here itself".
Rehabilitation can cure compulsiveness or if he/she experienced great loss, that is the perfect time healing arrives.
I agree that sometimes too big a loss can wake you up and that is a good time to re-evaluate yourself because no matter what anyone says as long as we are in the gambling trap where we loose some money win some loose more repeat we would never understand how much we are actually loosing. But once we loose a big amount suddenly we realize like "oh man what have I done?" that is the feeling that can help you exclude yourself from gambling.