My friend has sent me a payment request for the wine I brought to her house.

I took two bottles of wine to a friend’s house on Saturday. On Sunday she sent me a payment request for £8.40. The explanation was “your share of the drinks”. I assumed she had bought something else after I left. She had not. She had added up the value of all the wine consumed and divided it between the six of us. This included the two bottles I had bought and physically carried through her front door. I said, “I think you’ve included mine.” She replied, “Yes, I’ve included everyone’s so it’s fair.” I have spent the morning trying to work out which part of that sentence I am failing to understand. Apparently bringing wine is a gift to the host. Once gifted, it becomes part of the shared drinks. The shared drinks are then divided by six. I asked at what point the host pays for them. She sent a laughing face, which did very little for the arithmetic. My partner says to pay the £8.40 and forget it. He is a lovely man who once paid for a subscription for eighteen months because cancelling involved a phone call. I am taking his advice in that context. I am not normally a receipt person. I have happily paid for taxis, birthday cakes and a round in which somebody chose champagne after everybody else ordered beer. But I cannot quite bring myself to buy back a sixth of my own pinot grigio. Should I pay to preserve the friendship, or politely ask her to deduct what people contributed before splitting any balance? She has invited us again next month and said not to bring anything this time. Excellent. I look forward to finding out how much that costs.