When gambling stresses you out it's a sign that you are doing it wrong and perhaps it would be better to take a break for a while in order for you to get your mind right. Gambling is a game of entertainment and shouldn't be used as a plan to acquire wealth, one of the reason why people get frustrated with gambling is because they put their hopes into it probably because they think their games are well analyzed or they got a paid prediction, this makes them go all in by staking huge amounts of money hoping to get a significant reward but most times they get disappointed. Gamble responsibly and just do it too have fun.
You're right you know even those people who are gambling for fun also get stressed out, probably when their favorite team isn't performing very well. Of course this always happen in gambling, when you bet on your favorite team and you find out that their performance is not quite impressive or maybe they're losing. at this point they can get disappointed and decide to Walk away, not because they didn't get the outcome they were actually expecting, Rather they can't just seat and watch their favorite team losing.