You have to realise it's part of the game, I've often become really emotional & depressed or stressed myself cuz of bad luck, or stupid players etc..
But then I tell myself it's how this game works, the aspect of luck, variance is all part of it. If you don't want that then you shouldn't play poker at all, perhaps. Donkeys that will do stupid moves & get lucky, all that too, you gotta embrace it to keep on playing your best game.
Oh & there wouldn't be so much money to be made in poker if it weren't for the gambling & getting lucky aspect which is ofc, addicting too. I realise if poker was a game pure skill, no luck like chess for example, it wouldn't be so interesting or profitable.