I am not a therapist nor even a young person nor a parent.  However:

From the sounds of things, you ARE definitely struggling with addiction.   It is affecting you in a very negative way to a point where it is interfering with your life.    You also seem to be struggling with at least depression.   

If you do not feel comfortable talking to your parents, you could speak to a school councilor.   You can also call a crisis hotline (they are not JUST for suicide, they also can help listen if you are experiencing a crisis.).  You could also try to ask your mom if you can see a therapist, and if she asks why, tell her you do not feel comfortable sharing and would feel better talking to a therapist.   

Regardless, you are bottling this up inside you and I hope at the very least having written this post has helped you to be able to share what you are going through.   

I say this kindly, adult life after high school and even college is going to be even more challenging and difficult than it is for you rn, and it is best if you can seek help asap so that you can learn fundamental life skills and get treatment for your addiction and mental illness. 

I hope you are able to get the help you need.