I am reminded of the clinical term used to describe the typical stages of the grieving process. For me, losing at trading can be as emotional as losing a physical object (or person). The letters are DABDA.
Denial: this isn't happening to me (again).
Anger: how could this happen, I should know better, what an idiot I am!
Bargaining: maybe it was just a mistake, maybe they'll bust the trade (LOL).
Depression: I lost again, I'm a failure, I need to quit trading and get a "real" job.
Acceptance: I screwed up again, what can I learn from this, and how can I avoid repeating the same mistake?
I am not always aware of this process as it is taking place, but usually see the stages in hindsight. When I suffer an especially tough loss, which does happen occasionally, I try to allow myself to go through this "grieving" process. As they say in AA, "This too shall pass."