Mom v.s. Grades? How can I win her okay for Cs? I don't even want to go to college.?

[Christie]

My mom and I have a complicated relationship but let me jus sum it up real quick: she wants me to be just like my brother (made it through highschool with a 5.0) he has been accepted to an amazing college and he is the ideal child. Then when it comes to me information doesn't stay with me so I do really bad on tests and quizzes. Then my mom gets frustrated and upset and yells till I start crying. I have actually self harmed and I think I have depression but my mom when she found out I was cutting she said "it's just because you heard bout it from a movie" this upsets me because she can't accept the fact there is something wrong with me. It's not like I'm stupid I just am not good at things I'm not interested in. Like math sciences or reading. I fit in with acting talking and social things. I have gotten Cs on my report card and my mom has taken away my phone, facebook, twitter, etc to motivate me. None of this has worked. I'm not sure how to tell her how I feel because we are not close at all and have a horrible relationship with each other.