That seems like a very important component of your "edge". NOT trading can be difficult. I've identified mine as FOMC days and half days as well. Admitting something doesn't work and having the discipline to implement such a revelation into one's strategy is a big step on the road to success. IMHO.
Sometimes I have the same thing. Although sometimes it is just a complete opposite. The best advice is to shut off the PC and just walk away for that day.
take a look at GLDN today. there is money to be made in that one. nice chart and was upgraded to buy at merril lynch and initiated with a buy at citi bank with a 141 target. it has 9% short intetest which will be exaggerated on a light day such as today. i'm looking for at least 101.50 on GLDN today.