Share your insights or perspective on the financial matter presented in the input.

One of my stocks dropped 40% in 2 days, how should I mentally approach this?
There are 2 approaches. One of them is already mentioned by @Afforess. If the approach by @Afforess is not feasible, and you can not see yourself making an unbiased decision, close the position.  By closing the position you will not get the best price. But by removing a distraction you will reduce amount of mistakes you make in the other stocks.