Why get upset over some online communications?
I would be concerned over a physical or face-to-face dispute.
Well, I do think that sometimes online communication can be as stressful as face-to-face disputes. At least in a face-to-face situation you know the other guy and can confront him directly. And there is a greater chance of resolving the issue.
The thing about online discussions is that encountering hostility can be a bit unnerving for new forum users because the whole interaction is faceless and there is no physical proximity... while this can make one feel safer, it can also lead to frustration when seemingly simple issues which one tackles over real life over a cup of tea cannot be taken up due to various constraints like political correctness, cultural misunderstandings, the limitations of textual communication etc. etc.