Have you ever reacted defensively but regretted it?  When someone has a wrong idea of you, it’s easy to sit in a place of defensiveness. But when reacting from that place, people might not hear your actual message, and instead notice behaviors and mannerisms which undermine your message.  Use your body’s reactions as signals and indicators, to distance yourself, and then look at what’s really the piece that’s bothering you.  That way, rather than having to defend yourself, you can deliver your message, and demonstrate who you really are.