If you realize you've done something you're not proud of, you've just got to watch yourself in the future and try to make up for whatever damage you might have caused. This is as true for me as anyone else. I've never enjoyed the realization that I've made an ass of myself, so I generally try to keep myself under control. (Should it involve something like, say, putting a troll on "Ignore" until you can read vis posts with cool detachment.)
I never really ignore the posts made by others on forums, since they have as much of a right to post there as anywhere else. Despite the fact that at times I can become heavily agitated at comments of particular people, this irritativeness runs only skin-deep. Life has taught me a hundred times over that general and initial observations mean nothing at all once you truly try to understand someone else.
How much better you express yourself than I. I know that the vehemence of my post was uncalled for, truly I do, but nobody enjoys having their hobbies and interests criticised
An apology is sufficient enough, you don't need to feel any further guilt. Everyone makes mistakes in life, even if it is concerning something which they are adept in. This is another factor of Evangelion forums which I enjoy to a great degree:
forgive and forget. Apologies in other places can be quite rare thanks to people being so reliant on their pride that they blindly follow their own intuition and ignore everyone else, but at least in places such as this others can be more admittant of their own errors and flaws. Perhaps Evangelion has taught us something regarding what matters in life after all...
The primary thing to do, I feel, is to remember to go an drink deep from a mug of coffee before writing a response. That gives me just long enough to realise that however offensive I might find what a person is saying, it's not worth getting into a flame-war. Especially if they didn't mean it in that way.
Whether you're having a bad day or simply tired out of your skull, the best thing to do is to maintain your composure. Humour helps to counter this problem immensely, and it is always best to attain a more positive reaction, which also helps influence others. Nobody needs to be the fanatical skeptic or the negative critic to gain acknowledgment and respect from others, and conflicts often cause people not to post or lose interest in the subject entirely, which is never a good thing.
The Internet is always limiting us to draw our own perspective regarding a person's state of mind when they discuss something, and this can often be misinterpreted. People should always bear this in mind.
This is Dr. Phil, signing off.