In all games, we all win and lose quite often. Nothing wrong with losing. When we lose, it helps us realize what mistakes we did and how we can learn from it. Not just that, but losing helps us better form our strategies by seeing what works and what doesn't.
If you want to win, you must first want to lose. Because by losing duels we can learn a whole lot about the game itself. Losing helps us win.
So next time you feel like getting angry at a loss, relax and think back about what made you lose. Was it a misplay? Perhaps it was something your opponent did to counter you that you didn't prepare for? Perhaps you underestimated your opponent? All these and more can factor as to why we lose.
But once we realize why we lost, we can begin fixing our mistakes and get closer to winning.