If you believe something that is a belief. That's how the English language works. Nothing to do with how well founded that belief maybe. The one word fits all sizes.

You sincerely believe, I am sure, that the responses you evoke are assumed, and that those responding in a way you describe as defensive do not actually experience what you write as attacking. I believe that is a mistaken belief on your part.

There is no difficulty in any of us being open about our beliefs without trying to impose them on others. Try it.