Friendship Advice- how do I handle this? Me- F40, friend F39, friend F40

Me F40, friend 1- N F39, friend 2- S F40

BWT, I need advice on some friendships.

My one friend, we will call her N, lives close by, and we hang out occasionally. We are both married with kids similarly aged and I work full time, she doesn’t, but she has a busy jet-setting life. We mostly hang out because I’m the one making the effort- let’s do a girls dinner, let’s hang out with the kids etc. she rarely initiates. I’ve come to terms with that.

S, is her friend who lives across the country and I know S as well. We aren’t super close, but close enough to to warrant a girls trip in a few months.

This past weekend S came into town with her kids, and N and S got together with their kids… I feel really hurt.

I’m going on a girls trip with you two, and you got together with the kids and didn’t invite me… also, N is able to make plans with S, yet I need to initiate and schedule in advance to hang out?

I don’t want to cancel the girls trip, but this makes me feel sad. How would a BWT handle this? I really like N, and friendships are hard to make when you’re older… in the past when I have pulled back from N, she wouldn’t initiate.