I have been seeing dp for 9 months. It's my birthday in a few weeks time and I have 3 friends who coincidentally have birthdays within a week of mine so we always do a meal for our combined friends (6 couples plus me).
I told dp about this date ages ago. The restaurant where we are going needs pre orders so I asked him last week and he said oh sorry he couldn't come because a friend of his who he hadn't seen for a year had announced he was over from the US and only here that one night and he needed to see him. I was a bit pissed off but thought fair enough. I thought I would double check so asked again yesterday and he had clearly forgotten his first excuse as he told me something different 
Now if he didn't want to come I would rather he told me. I feel a bit of a pillock as these friends haven't met dp and I thought this would be a good chance etc and now I'm the only one going who isn't in a couple. I wasn't actually upset until today when I had a chance to think about it.
There are some other niggling things just not right - AIBU In seeing this in a pretty bad light or am I being a bit over dramatic?