I really would try and stress about it and just accept everyone has different views on this.
I used to feel upset that DH's family never included my parents in things when they always did and I asked them why. They just said they liked to keep celebrations (other than life changing events like weddings) to their immediate family and friends. And I also suspect they don't really enjoy my parents company (if I'm being really honest now). It's contradictory and hard but that's how some families operate. I just gave up a long time trying to figure it all out.
I think you need to let it go. They aren't related, maybe they find it odd they were even invited.
Don't worry about them, have a good night and have fun!
If there is a long history here maybe none of us can really comment but based on what you've written it sounds to me like you are far more invested than they are.
Are you close enough to them to ask them (once your mother's birthday is behind you) if there were other reasons why they didn't attend. If you are as close as you say you are I would strongly suggest you do that.
Sorry I reread my post and I hope I don't sound harsh. Your OP just reminded me so much of the angst and heartache my DH's family used to put me through, and I used to second guess everything all the time.
Hugs it is hard when you hold family events very highly and other don't feel the same.
We have lived away from our families for close to 15 years now and I hope to create that sense of family in my own family as they get older.
Yes, I would be annoyed, a similar think happened with my ILs and my mums 60th.
What made ours worse is that we paid a deposit for a full table and then they changed their mind. We also did everything together.
This was a few years ago now, and we just don't bother with them now. They pick and choose what's convenient for them. We can't force them to come.
My advice is just to let it slide and don't expect anything from them in the future, just don't take it to heart. Enjoy time with your mum and leave it at that. It's their loss.
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