It may sound petty, but two months ago my neighbour had a coffee morning (I wasn't invited, fine, we aren't best buds or anything), and she asked me if she could borrow some teaspoons. I lent her four, and she gave three back a few days later. They were wrapped up inside a napkin so I didn't notice until she'd gone that one was missing. Time just went by without seeing each other so there wasn't a casual opportunity to mention it.
I know it's only a teaspoon, but I feel really angry that she has basically stolen it. I don't feel I can mention it now because it's been too long and it is only a spoon, but I feel angry everytime I make a cup of tea and am reminded. I can't help thinking she must know. They are quite distinctive sppons, she must know when she sees it that it isn't hers.