A few days ago, DH got a message from an old friend (not a close friend, we last saw her about a year ago), these are the messages (anonymised some details).
Friend: Hi (OP's DH). Do you fancy coming to see (obscure 80s band) on 31st August? The gig is at 7:30 PM at Y venue, and the tickets are on me.
DH: Hi, actually we are meeting Fred that evening in X pub, and to be honest I'm not a big fan of (80s band) anyway. The pub is quite close to Y venue so maybe you could pop in for a drink with us before or after the gig?
Friend (1 day later): OK I have confirmed the tickets for the gig, i've bought two tickets, it's on me. Shall I meet you at the venue?
DH: hi, no, we cannot make the gig. As I said, DW and I am meeting Fred in the X pub that evening, I think there has been a misunderstanding.
Friend: oh no, I won't be going then, waste of money.
DH: didn't you see that I said we are meeting Fred that night?
Friend: yes I did, but the gig is only one hour
friend: oh well, I might come to the pub and pop out to the gig for a hour.
When DH told me about this, I thought it must've been just a misunderstanding but I've now read the messages a few times and I'm completely baffled - there is no ambiguity in DH's message, I just cannot understand why she went ahead and booked tickets! So weird! 

Anyone else experienced any similarly strange behaviour?