Mr Goodbar, try this. Sometimes it works just to fill-out the "order execution" ticket. The inscrutible cosmic forces that control these matters sense that you're READY to sell and, thus, the stock tanks in order to panic you!
Then, very quickly change the "sell" to a "buy"! You'll add to your position at a better price!
If that doesn't work try this: Take a 2 week vacation from trading. And if that doesn't work - quit!