Well its very tough decide when to stop.everyone have their own goal first you need to setup your goal.you can fix how much you want to got profit and how much you want to lose.Do not play gambling for long time,play gambling for long time have bad impact you can lose you confidence and lose money.do not invest all your money on gambling,you just invest how much money you can effort.thanks
For me it is not that tough to decide when to stop. As long as I still have money to gamble I will going to keep on gambling. And the right time to stop is when I lose everything and I don't have something to gamble anymore. But of course when the time of winning is coming, I will just stop if I get the amount that I set upon winning.
I think it's wrong, winning in gambling is very rare, and you said you would play until your wallet become empty. If you do like this, you will not able to make a profit in gambling, and also you will not save your investment. Fix the amount and play only that amount if it exists just stop your play then at least you will save some money from your wallet.