I went to drop my 2 DC's at their dads at 5pm. It's about 15 miles away from where I'm temporarily living with DP. Discussed getting steak and wine for dinner with DP. Whilst I was out I got a text from my old school friend who I haven't seen for ages asking if I would like to meet him in our home town for a quick drink (the place 15 miles away). I declined because I'd arranged to have dinner with DP (even though I'd love to have gone because I'm missing everyone from my local pub!) and we don't get to spend much time alone as one dc is sleeping in our room at the moment.
Got home with the steak and wine and DP's friend is here and looks set in for the night 
he's a conspiracy theorist who frankly bores me to death and they were playing Fifa on the PS. I'm in the bath feeling quite pissed off.
I text DP (from the bath) saying 'wish you'd let me know as X asked me to meet him but I said no because I thought we had plans?' He's ignored me. Which he will because he will want his friend to stay.
AIBU for being miffed? I feel like he hasn't extended the same courtesy that I gave him. Not to let down on our plans (and I bought the steak and wine which I was too skint for really, which will probably be left now).