The best way which works for me personally is to consider those as just a game you should not think about those numbers on the screen as you're actually turned or lost money, only money which is earned is the vipers that you're holding in your hands.
In my own opinion, most of the people has the problem of trading based on their emotions and not through the market situation so they lose their investments every time the market price is dumping on the market by selling at the lowest price.