Went to one of my closest friends DD's 4th birthday party at the weekend and when we turned up it was a pirates and princesses themed party and all the children were wearing either a pirate or a princess costume. My friend didn't mention this at all to me when she told me about the party. I took DD 3yrs with me and I felt bad for her, but she was OK as she was wearing her special party dress anyway and she's not really into dressing up like a princess anyway (although she would have dressed up like a pirate!). My DS who is 5, was also invited but I didn't take him and I know that he would have been upset to have been the only one not wearing fancy dress.
AIBU to think it was a bit careless of her to not mention this to me? Potential of the DCs getting upset?
She texted me the time and date, whereas she gave out proper invites to the other children (mostly from nursery) stating the theme.
I travelled a long way to get the party, much further than anybody else, so feeling a little bit hurt by this. Not a major issue though, not holding it against her, I've already sent her a message thanking her for the party and that we'd had fun. Just a bit 
.
AIBU?