As-Salamu ‘Alaykum sister,
You have presented a lot of issues. It seems you have an immense amount of pressure dealing with parental expectations, school, and your own selfhood. Unfortunately, I will not be able to address them at length in my response but will provide some general advice.
Consult with a school counselor about all the matters you described. If you do not have a school counselor, then seek an outside counselor.
Your parents should be concerned about your matters and think beyond just your academic performance. Consistently go to them for support and help. Keep explaining to them how you feel and that they should not see you only as an academic investment. Speak to extended family members like aunts and uncles as well. Generally, the family has your best interest at heart and will get involved if you remind them of the severity of your negative experiences.
Research online for tips to deal with bullying. There are many articles which address bullying as it is also an issue in the Unites States. Try these as a start: http://www.bullying.co.uk/ http://www.bullying.org/
Regardless of how bad you feel, keep practicing your relationship with God. Things may not be easy now, but with time, they always get easier!
“Indeed, with hardship [will be] ease.” (94:6)
Consider going to another school if your issues persist. Sometimes, circumstances will not change until you change your atmosphere.
Finally, remember that your life is not only defined by academic scores and education. You also have to remember to get good scores with God above all else. You are here to serve God and everything else is a means to do that.
May Allah (swt) help you,
Disclaimer: The conceptualization and recommendations stated in this response are very general and purely based on the limited information provided in the question. In no event shall AboutIslam, its counselors or employees be held liable for any damages that may arise from your decision in the use of our services.