Back on topic, you cant really say that we should not being too emotional but these things cant really be avoided yet we are risking out our money that's why its normal for a human being.The thing here is that on how you gonna handle in times of this one. There are lots of ways on diverting your attention into other stuffs.
If you are dealing with a huge amount of money, it is emotionally draining when you see your investment going down, but if you have entered the market when the price was low then there is nothing much to worry, all my investments in this market are in profit and i really do not care when the price crashes in the short term, i am just in it for the long term and if there is a major correction i will evaluate my positions.
Not all situations of traders would be similar as yours which there would be always an encounter either emotionally draining because of seeing your portfolio going on red or deep loss on a bear market.If you do already holding up for longer or lets say years where the profit was just enough to cover the bearish trend then that would be good because you are not stressed since you are still seeing positive but on over all its just like the same because profits would be still on loss.