Hi there,
First of all I am sorry to hear that you are going through such a horible thing. One thing you should do right away is mention that to your parents, whichever one you feel the most comfortable with and in this situation it's usually dad. I have had alot of experience with being bullied when I was younger, I felt hated, disrespected, neglected, like nobody cared about me.
You need to talk to someone about it - it will help!
Another thing that you need to do is something to boost your self confidence, when you're being brought down it's important to do something that will give you a huge ego boost for yourself, this may sound silly but it's true. I took up martial arts, after a couple months of being in martial arts doing boxing and jiu jitsu, I have found much more peace with my inner self and was so much happier with the things that I was doing with my life.
My heart felt good, I felt good, and I felt like I could beat up any one of these bullies, and I eventually stood up for myself.
The day when you're so confident with yourself, and love yourself so much, that you're ready to do what it takes to stand up for yourself and be happy, you will do it, and it will be the most amazing feeling ever.
Trust me man, give it a shot!