Is it me or is it just HARD to make mum friends

I’ve been trying to make mum friends for a while now but it just ain’t happening! I say hello to a bunch on the school run but that’s about as far as it goes. I’ve been out for social drinks with a group and I get a along with quite a few, but then not invited to subgroup drinks or socials or group playdates and I know my child is good mates with quite if few of their kids. Can’t quite understand what’s going on. Feel a bit down about it. How is this working out for you’ll?