*Scrapped the whole thing because i replied so fast that i didn't write it the way i wanted*
The thing is,i don't mind at all being competitive or others who do so.I actually like it,it's what makes it fun after all.
About the KD ratio,it's something that just shows you how good you are,it's up to you to take it too seriously or not.Most of the times i don't.If you will take it seriously enough then yes,it'll be tiring and will turn the game into anything but fun.
Now,about the jerks online.It happens,it's simple as that.There are in online gaming,in forums,in blogs,in real life etc.With other words,everywhere. xD You can't avoid that.
However-when i was playing COD4 (PC) i can't say that there were lots of times that i met jerks in-game.Now that i play a free FPS though,you can't imagine...
So,to wrap this up.When it's about the jerks,online or not,you can't avoid them.About being competitive though,i like it,it's fun.It's just how seriously someone takes it,for instance: If you'll play a basketball game in your neighborhood and in the end your team will lose,will you be bummed about it?Will you get angry?If yes,then you're taking it too seriously.
Anyway,this is all about POV.I preffer playing online because it's competitive and because i get to play against different people with different styles.It keeps me interested.