Try read up about trading pyschology.
It is pretty well-known that after a sudden loss of 15 to 20% of your equity (e.g. stake in a poker game, an open position with draw down from its all time high, etc.), most people goes into denial mode.
Nothing matters until after,
1. the position is liquidated
2. the position return to exactly where the hoper wants
#2 is interesting because that changes over time - from back to the old high (the best case), then down to breakeven at level before commiting the position (the not feeling bad case), then down to an acceptable loss (its painful but acceptable), etc.
Now, think hard and take yourself out of the position for a moment. Can you skip the part of denial and going straight to the point where you can think of your acceptable loss?
Then think about what is an unacceptable loss to you.
There, you will discover what is the correct thing to do.