Hang in there buddy, I understand where you're coming from.

My thoughts are that if this person has heard your explanations several times but continues to misrepresent you very negatively, then the way to stop over-explaining yourself here, is to end the drama: say goodbye to them. That can be your final say with this person. That's my view and my approach based on what you've written here. Peace of mind and a calmer soul are as gifts.