I just ragequitted in a CS GO competitive match, and uninstalled it. I'm not a bad player, my rank is Distinguished Master Guardian, and I only have 45 hours in the game. Had some bad games of course.
This has happened to every competitive game I play. COH, LoL, SC2. They get stressful, which causes me to be pissed, then causes me to be tired. They get addicting too, "maybe i'll play another" and I end up playing 4 more in the end, and then takes up so much of my time. Worst part is they get so competitive where I'm actually playing only to win for my rank and get more skilled rather than have fun. Some long matches also requires a s***bucket and a pee bottle, I hate that. When I do win, yeah it feels satisfying and somewhat fun.
Now that CS GO is uninstalled, I currently play no competitive games, frees up my time, and I can play more relaxing games instead.
I prefer a challenge so I do like competitive games. With that being said I don't put all my time into a game anymore, I really don't have the time for that like I did 10 years ago. I look at it like no matter how bad I'm losing it's still a chance to get better at the game.
... sorta. I quit WoW for the same reason you quit whatever it is you're talking about. I used to have fun doing the pvp. In fact, it's all I did. After a while, the fun wore off and I was just doing it because my competitive nature had taken over. The rage and frustration random people can cause you is outstanding. The things they would say still blow my mind to this day. Anyone that's experienced wow pvp knows what I'm talking about. That alone had lowered my opinion of the human race quite a bit.
So I avoid anything similar. I've never played Team Fortress 2 because of WoW for example. I'd rather play lighthearted competitive games that reward the experience with fun then with something else like gear if you grind for 2 months. Like Bomberman or something.
I've found that I very much dislike competitive games in general, but love the heck out of Team Fortress 2. Probably because most servers have much less pressure on you to perform well, though I do usually end up in the upper-half of the point scores. It's particularly great if you find a server that has silly people with mics; it ends up being a game of socializing while you shoot things.
I've also found that one tends to feel better after playing single-player games, though, if that makes any sense.
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Personally I have never liked competitive/PvP games. Halo on the old Xbox and World of Tanks is honestly the extent of my PvP. I play EVE, but not for the PvP. Though I do plan to get into the low/null sec areas more soon, but it would be more of a co-op venture with corp mates than simply seeking out players to gank.