To be afraid is good, after all, it will help you to be conscious towards excessive risks.
However, you should learn the contexts of proper financial conduct and money/risk management in gambling before you do anything. Also, ensure you gamble only with the money you can afford to lose and have a good gambling plan, and be disciplined to stick to that plan regardless of the situation or how you feel at that time.
There is nothing complicated about it, you just always follow this rule. Breaking it is simply forbidden. And this alone can save you from many problems, big losses, bad moods, excessive emotions, and much other negativity that you will experience if you lose more than you can afford.
And you think it's as easy as you said? Fine, it is the right thing to do, and if done correctly, the gambler will surely limit his losses and perhaps enjoy gambling and stay in profit. But it is not accurate to say that it will save you from the psychological problems of gambling, only being disciplined and determined can do that. This is why you would see a gambler having all the needed strategies, management and plans, but still going astray. Emotion and other psychological distractions are more powerful than you think.