Please give me an honest opinion

My baby shower is tomorrow. My MIL is throwing it we live 8 hours away and she said my 5 year old step son has to go. She's already turned it into a birthday party for him but that's a different problem. I know a handful of the 40 people coming so I assumed my husband was coming because my stepson doesn't listen at all to me and I don't know anyone. My brother in-law has a dirt bike race he's racing in tomorrow and my husband wants to watch but I'm about to cry at the thought of doing the shower by myself and knowing how his son will act. Am I bring mean for not wanting my husband to go to the race?