I frequent a few forums and message boards and now and then I will answer a question or put forward an opinion... and inadvertantly upset someone or just get on the wrong side of them. I really hate this because I'm not a confrontational sort of person. It is very difficult when you are just dealing with the written word to make yourself fully understood in the way that you want to... I have a bit of a dry sense of humour too and sometimes that doesn't come accross too well either.
Plus... once you have hit that send button, it is very difficult to unsend it.
Lifes to short to worry, but I know what you mean. As you get older, you will realise that things turn to your maturity level, and you tend to express your thought and feelings in such a way, which you may or may not regret later, and especially after you have pressed that send button, verbal or otherwise. Personally I am at the 'tender' age, when I don't give a dam to most things .Take a point in question. You only have to look at Gandalf the magician [grumpy but sensible and wise 'person'at times ;o)].
What brought this on then, someone been having a go at you, which we should perhaps know about!.