Quote from Ripley:
Taking losses isn't your issue. Its having a winning edge. Thus, there is a higher % that a trade will go against you. It could also be that you are risking a little too much on a single trade than what you can stomach.
With that kind of odds, even the most disciplined traders would have a hard time taking losses. Trade smaller, develop a winning edge.
Perfectly stated.
The original poster who scalps and has a hard time taking losses simply has no strategy. Specifically, no strategy that is based on statistical significance.
Develop that and you will know when an open loss is mere noise or an indication that you are wrong. Tangentially, you will also become much less fearful.