I thought I'd take a moment to outline Diplomacy game conduct, as I know that there are a number of youngsters who play but are unfamiliar of the proud (face-to-face) tradition of the game.
Diplomacy is a game played by men and it is forbidden to show emotion during the game. Emotion is the province of women or metrosexuals. It is best to stay cheerful. If somebody backstabs you, you are meant to chuckle and refer to your betrayer as a "sneaky dog," smirking pleasantly to imply that you're immediately planning their undoing.
You must expect to loose each game. Diplomacy is a contest that produces, in some games, six losers for every winner. The elusiveness of victory is what makes it appealing.
Loosing your temper simply isn't done. This *pauses* game play. Game play principally involves negotiation, which is slow going when one party is having a feminine tantrum. I have only once seen someone loose their temper at a live game, and this person was later confirmed as a communist.
When you feel that you're not performing at your diplomatic peak, do not attempt to blame others for this. Diplomacy is amongst the shallower sports on offer, being part lie-fest, part stampede and part popularity contest. If you fail to secure the confidence of other players, the fault is your own.
The internet is not a place to hide behind anonymity. Winning or loosing, it's important to be a good sport.