AITAH For being upset my wife chose her late brothers friends on her birthday over me?

Today is my wife’s birthday. We have been together for 10 years and our relationship is for the most part good. 2 years ago her brother passed away in a motorcycle accident. Her brothers friends have become more apart of our lives than I think is normal, mostly due to her mother inviting them to everything as a coping mechanism, but I try to accept it for what it is. Anyway, we spent today together with our kids and planned to order in and watch our show and spend time together tonight. This afternoon she asked if she could meet up with her mom and the friends at her brothers memorial and have a beer. Somehow that turned into going to her mom’s house with all of them, and she isn’t planning on being back until 11, when this was supposed to be an hour. I don’t want to be a jerk on her birthday, but am I wrong for feeling a little hurt that I’m home alone with the sleeping kids and she’s out with them?