Lol, OP is baby. This is typical CoD behavior. If you're annoyed by it, you should just leave the room or something. CoD and Halo are some of the most frustrating games to play due to their competitive nature and health system (CoD is pretty much seen = dead, Halo is all about comebacks in firefights). People try to do well, die, and get angry that they weren't able to do well, usually blaming it on a game element (in CoD = Perks/Guns, Halo = Power Weapons/Vehicles).
I have a friend who is probably the most quiet, nice, reserved guy I've ever met. However, when he plays these sort of games, he turns into a completely different person. It's really quite amazing to watch.