Attachment to trifling material things

Just a practical question on attachment to trifling material things. I struggle to put it in words but from my younger age, I have a habit of being angry when someone takes a minor item without asking. He/she could be my best friend but still, the feeling is there. I don't think it been stingy because been asked or not even asked I would give the same person or even a stranger x100 times the value of the item but when taken without my consent it is all a different matter. My question is how do I get read of it? A thinker once told me: if you claim to not-care for these things then when someone takes these items and you feel the anger go burn two more of the items to show that you're in control... this method did help me to quench the anger, but the character still lingers? Many Thanks.