I absolutely hate my grandma
What is your reason for hating your grandma?
She always gives me gifts I don't want. She doesn't treat me well enough. And she's, frankly, dumb.
I'm sorry you feel that way, but you can't dictate what gifts someone gives you. You should appreciate whatever gifts you get from your grandma and enjoy her while she's around.
I don't like what you just said. I'm too good for you.
Disliking your grandma because of gifts she gives you is just kind of low. Holding hate in your heart is not good because it will simply take away from how present you can be in life. You and your grandma should talk so you can find a way to love her.