It's joyous to make gains in trading. The problem is how does one control his mind when there is a huge lose
If you engage yourselves in trading (or in other investing opportunities) its a must to have knowledge and aware of the risk and possible consequences.
We cant expect to always profit, there are times we lose and its inevitable in trading no matter how skilled you are. Thus if you cant bear to lose your money then simply dont trade. Its somehow similar to gambling because we cant predict accurately if we're going to earn or lose.