As the questions says, when do you stop? your point of no return?
a. at least double your money, then stop
b. you only stop when you have lost all your bankroll money and then blame the casino?
c. or you are a superstitions gambler, when you have signs like losing 3 straight in a row, then you quit because you know that you're having a bad luck
d. you stop when you are at least break even
I didn't include chasing your losses as obviously you might to continue.
Sometimes I stop after I doubled my money, sometimes it's after I've lost all and, but a gamble addict doesn't have anytime to stop, be it good or bad until he's lost finish, being a superstition gambler doesn't guarantee your stopping at that moment, there's some kind of lost you will get quiting at that time will be very difficult because you've really lost beyond your expectations and then you start chasing lose and keep losing, so stoping is a thing of the mind it only take the strong minded people to do that as a gambler and an addicted one at that.