So...
DP had a female friend, they were good friends but she moved to New Zealand (before we met) so the friendship was the 'How's the family' type whatsapp every couple of weeks and a phone calls maybe 4 times a year approx. Connected on social media, that type of thing, tbh she was barely on my radar, beyond someone he used to know.
Fast forward she went through a divorce but has remained over there, with no plans to return, but she started messaging and calling more frequently, wanting support and to talk. DP was fine at first but it got a bit 'aggy' if he didn't reply soon enough she would make jokes about 'are you still alive' etc and this moved into comments about social media 'oh I can see you are on Facebook but not bothered to message me'...
DP had his own issues (parents ill health) plus the time difference made it hard and as they'd not seen in other in years he didn't want to up the level.of calls. He tried to cool things gently, explaining he wasn't always free to chat and explaining what was going on, but it was met with low level snark 'fine, but I'm having a tough time too and need your support' etc.
Last weekend we were away, celebrating an anniversary, it was on Facebook so she knew we were away and why, and he got a shitty messages that he didn't call her up to say happy birthday. He replied to say we are away but happy birthday and got no reply, but then a week later got 'I can't believe you still haven't called since you forgot my birthday'
At this point DP sent a firm but polite reply saying he feels like the friendship has run its course and they no longer have common interests so he is going to stop responding. She had a huge reaction saying she can't believe it, she is devastated and will reply once she's had a chance to 'get over the shock'...
I've seen all the messages, DP showed me them readily after I expressed surprise at the strength of the reaction. He asked me what he could have done differently to avoid the upset and drama.
Aibu to think she is the unreasonable one here? Personally I'd only react that way if it was a close friendship not an old acquaintance. DP says they have never had anything other than friendship and I believe him as he has always been very open and honest.