ST, I am sorry. I think anybody would have been upset by that. I was upset reading it.
It's awful when an adult takes their own immaturity and frustrations out on an innocent child.
Isn't it just incredible how every interaction with a Difficult Child is laced with drama and chaos? There is NOTHING simple when they are in full form.
I agree with Tanya and daze. Setting boundaries and getting outside viewpoints to help determine what those are is about all you can do here. You can't fix this.
And I know you want to see your grandson so limiting that is probably not something you want to do.
Keep it simple. When people act awful and we have to stand by and watch, it is very very hard to do.
Congratulate yourself on all of the progress you are making, and now...be kind to yourself tonight.
You deserve it.
Hugs.