Mum friends or fake friends?

So I’ve become friends with two other mums and everything was going fine for a while. Then I’ve gradually noticed little things like planning play dates with the kids always on the days I was working. We then decided to go on a vacation with the kids, I mentioned what time I would be arriving (later than them as I couldn’t leave same time as them) for them to be out during that time taking their children to the one place I wanted to take my child the whole time and was never allowed to go there with mine. Although it absolutely infuriated me, I genuinely had a nice weekend over all. Fast forward a few months, I’ve changed my working days, I’ve been trying my absolute best to get involved and I’m constantly feeling the odd one out or feeling that I am being ignored and my child is made to be “less than” their children. Constantly being ignored in the group chat, play dates being planned on days I can’t do despite saying in the group chat I can’t do that, feel like my child is being shunned because they are at the same milestones as their children despite being the same age, absolutely no interaction with my child however I am always interacting with their children. Why cant I just find some friends who genuinely show up for me and my children.