That is actually what I ever experienced, losing more, and gaining less in gambling. That is why I quit gambling. Because until now, I am still confused about how to be in the gambling well. I tried to learn about the strategy of betting and the game that I participated in. But I fact, I still lost more. I feel so dumb 
Maybe you don't learned your lesson while losing money because you already set in your mindset that you can easily win back what you've aready lost in gambling , and yet here it comes you already quit ng gambling , it is not about strategy it is about luck maybe you should try betting on sports even the odds is low atleast you can easily analyze team who will win and you can defeat other teams. If you want to gamble well then you should watch and learn first then try it to your self until you gain enough experience to do so and always follow your guts.