Can I get some advice?

I am having trouble with deciphering what is "rude" and what is acceptable in the social eye. Social eye, meaning social situations between myself and another person. It always seems like we are speaking a different language. I say what I think or what I feel about the topic and I know it's possible at times my attitude might appear a bit aggressive, okay I'm working on it, but, I don't understand how else to word things besides what I think. It seems to intimidate people, and I don't know why. Am I rude?