This is going to be LONG as I want to put in as much context as possible. Trying to keep it as impartial as possible but I'm upset and obviously see this from my perspective.
Old friend (20 years plus). Have been very close for years. Our daughters were very close though have drifted apart in recent years. Last year there was an incident in which her daughter (13) and another girl sent my daughter (12) unpleasant messages accusing her of being a snitch and a chav. My daughter was desperately upset as she had previously considered this child her best friend.
I called the mum (my friend) on it and said I wouldn't normally get involved but this behaviour was unacceptable and quite close to bullying in my view and I would protect my daughter from stuff like this. She was very apologetic and her DD was forced to apologise. All was resolved and we moved on superficially although I think her DD is understandably pulling away from mine as she grows up, but they still love one another. I accept that sometimes children grow apart, but providing this situation to explain the background. I love her daughter a lot but I think her behaviour is quite bad a lot of the time and she is quite undisciplined. I haven't explicitly said this to my friend but it may be obvious that I think it.
In February this year we went away together on a short minibreak (me, my friend and our two daughters). Trip was happy, fine and without incident or disagreement, apart from the fact that my daughter ended up in A&E with an asthma attack on the last night.
But on the way home my friend lashed out at me for something which in my view is unbelievably trivial and there must be more to her response than this: I failed to reciprocate buying a beer which she bought for me at the Eurostar terminal when we returned to London. When we got back home after the trip she sent me a text message saying she thought I had a "screw you" mentality towards her and her DD in general and this was an example of this.
Her portion of the holiday had been almost entirely paid for by her brother as a birthday gift. I'd paid for all of mine and my DD's costs and we split the costs of everything (food, drink, tourist stuff) out there. So there's no way she can have felt that I'd taken her for a ride financially or freeloaded off her. It was obviously about something bigger than the beer I didn't buy for her. I've asked her what it is and she reiterated that she thought I had a "screw you" attitude but wouldn't elaborate.
We basically haven't spoken since then: before her DD's birthday last month I sent her a message to ask what the DD would like for her birthday and she didn't respond and hasn't done since and neither she nor her DD have thanked me or my DD for the gift.
Clearly there is more going on here than this one incident and it's a symbol for something else more problematic in the relationship. I've accepted that for whatever reason this friendship isn't really working for her right now and have given her space: we haven't communicated at all for over six weeks.
But I want to try to understand what has happened and whether I am in any way at fault. My guess is that she is still angry about what happened with our DD's last year or uncomfortable about the fact that they are growing apart and using some complete red herring about buying a beer on the train as a fig leaf. But it's strange and very upsetting. Wonder if anyone else has any thoughts.