Easy to say but if you are in the situation, you will realize it's really hard to do what you've said. As if you'll feel good vibes if you are having a lossing streak. Of course you'll get stressed wether you like it or not, unless you are winning. Eversince I only enjoy the game if I won.
Well, if we look at it from individuals perspective in sports gambling, it looks like everyone wants to win and one persons win is the other persons loss so I think that there is no point in having any kind of certainty or huge confidence. Anyone can win making the other loses. So, this should not discourage you the least because you should be very willing to loose the money you want to bet. It no doubt needs you to be consistent and passionate.