This has been one of the majority problem in the trading space today most average traders who already have average experience on trading mostly have this state of fears in them, In the trading space many average trader have this fear of succeeding, this mostly happens to an average traders or business owners which they likely say, "what if one red trade takes it all alway" they suddenly become more anxious having that fear that they might start all over again.
Most of it is caused by fear they let fear and anxiety take the best part of them which make them predict about the future's of there trades, well this mostly doesn't only happen to average traders only but average business owners to are also facing this which its called the fear of successes.
How do i overcome this fear?
Likely i would say it very easy to overcome this fear
When it happens i likely advice, in every one month ever week choose a day off from your phone,device's and go enjoy your self go enjoy natures, go play sports hangouts with friends love ones without ever touching your phone or laptop.
This has work out for me but yours made be in a different position it help you to recognize that there is more to life than the endless chase of money and materialism.
This fear will always exist or arise when we trade short-term, this is not only those with average experience. In fact, in your quote above, one red trader takes it all, this is not possible for beginners who are just starting out, at least they already know or play it. Usually someone who has played or experienced short-term trading at least knows very well what the sensation is, he or she will not be careless in making their trading decisions. Set loss limits and use stop-losses to protect your capital this can help reduce the fear of big losses. Fear may not disappear completely, but with the right strategy and learning process, you can manage it and make more rational trading decisions