Would it be bad if I don't want to celebrate my mother's birthday?
Why don't you want to celebrate your mother's birthday? It seems a bit strange.
My mother had never celebrated my birthday.
I can see why you'd be miffed to celebrate her birthday when she didn't celebrate yours. But you need to be the bigger person and go to her birthday.
Shut up you. My mother was a horrible mother and I'm not visiting her on her birthday.
You have a right to refuse, but the problem is that you will be missing from the gathering and family members will end up spreading rumors and talking behind your back, which I think is not worth it. Just show up and pretend to celebrate. It will only take a couple hours of your life anyway, so it will be quick.