Is it normal to wish for my grandma's​ death everyday?

She has fucked up my mother's life until my mom got married. Ten years ago she came to live with us and I can't stand her anymore, cause my mother's social lifeunderstandsended because of my grandma. They say she has Alzheimer but she understand dirty things for example and never forget things she want, otherwise she just "forgets" the right things. She smiles and laughs when my mother is crying because of what she's doing with her, she enjoys being such a bitch and everyone thinks SHE'S CUTE. I get myself​ thinking about killing her every everyday​, but I would never do that obviously, still it's my deepest wish. Is it normal? I wish so much she just disappeared, but there's nothing I can do. I almost punched her like ten times, I normally take things from her hand when she starts provoking me (like pretending she's not hungry because she knows that she'll get bad if she doesn't eat, cause she wants to go to the hospital just for fun, and then I have to put food on her plate and she starts yelling and talking shit). Then I have these strong reactions of almost punching her, but I can't do that because I would bring so much​ sadness to my family and yet I would go to jail. I wish so much my grandmother died.