The pendantic kicking that OP's get on MN is SO tedious and distasteful.
So many have literacy, comprehension and nuance deficiencies.
We all 'manage' relationships with those around us, it is a common use of language 🙄.
Sorry OP that you got so many dud responses.
I think grandparenting is different for people.
Some are all in and it is their life.
Others are interested but on their terms.
As someone in my 60's with no grandchildren, I could see myself being the latter.
You have been given good advice.
I think you should give them space and let them get over their huff.
Don't chase them.
They have rebuffed you several times, so give them the space they crave.
I think you need to invest in your own age friendships and build up your network.
Then when things settle and they feel better you can tell them what your plans are and tell them they are welcome to join you if they like, but no pressure.
The smallie stage flys, so make sure you enjoy it.
Don't stress yourself trying to include grandparents that wish to be only peripherally involved.
People have different energy levels and interests in their 60's, especially as yours are makingba lot of decisions and life changes.
They may be feeling overwhelmed in their own lives at the moment with it all.
Good luck.