If you stop on a losing streak you are not doing martingale.
Also, if you have unlimited money you don't need to go to the casino.
Playing a Martingale system is a guaranteed way to lose money in the long-term unless you have unlimited funds and there are no table limits. That's the ONLY that the Martingale will work.
Casino's and gambling sites have table limits, which limit people from continuing their bets even if they have 1000's of BTCs, and this is another edge a lot of casinos have.