"We're not equal"

I dont know why, but my mom always feel the need to tell me that "were not equal" and im not "the same as her". I dont get the point of her telling me this, she sounds ageist and is basically saying im less than her because im 17 years old?? She only says this when shes trying to win an argument like thats going to change anything, when she knows shes wrong. I literally confronted her about it today and she just kept saying it. I dont know what I need to do to get her to realize how wrong that is to view me as an inferior human being, when shes the one dependent on me! She acts like shes god, and im one of her slaves and im sick of it!!! I dont know if she needs mental help (i think she does) but I cant take it anymore and I cant live like this. Any advice??