In my opinion, I think anyone who can't bear the risk of losing in gamble should not even think of venturing into it.
That's the whole point when someone is scared of losing money in gambling, they shouldn't get into it.
But we can't help ourselves when we have thought of gambling and we want to do it. There is no exact way how we'll stop ourselves but that fear really comes in any instance once we get involved.
Going back to the whole point, someone who gets scared of losing money, yeah don't gamble.
It's not going to be called gambling if risk is not present, of you are in fear of losing your money then better to stay away and find other way for your entertainment, or if you are thinking about making money then better to look for other venue of investment, gambling is not for you if you can't let your money go.
For those who can afford to spare their money for some entertainment then it's going to be good to keep that limit and not to exceed, it's going to be problem if you already using an amount that's not allocated with your gambling but intent for other important obligation.