Your realisation is correct; there is not a perfect strategy that will guarantee winning back what has been lost to gambling. The best strategy at that time to adhere to is to quit gambling for that day and not to make any further bets, as it will result in losing more, adding to the already lost one, because once our mood is affected, the type of gambling judgement we will make will be harsh, and the end result will always turn out to be negative.
There is one thing about gambling, you can't win from a casino consistently be it casino games or casino sport book. You can be playing one particular game on a steady and be winning but the moment they notice you are having winning on consistently, they immediately change some things that can make it harder for you to win again, if you are not smart enough to understand when to pack your bags into the next game, you will lose everything you won nack to the casino.
As a gambler, if you see an option working for and you know you are not cheating deliberately, you have to make sure to play it to fullest because time will come when the method wouldn't make you any money again. If it's the one you have another method to win, that's when you can run using that method to win without trying another error to win, that's what every casino person has to do if they really want to make money from casino but loss is something that remains constant.