please help... this is taking over my life

I've been a addict since age 13, Now I'm 17 and living with the side effects of my four year addiction. I learned about NoFap January of last year and I was amazed and was always contributing and helping other people out.... But that soon stopped and I began falling into relapse loops and eventually stopped visiting NoFap. After relapsing today I realized I'm wasting my life and that if I don't quit this addiction I'll end up alone with a job I won't like. I have big dreams and porn is stopping me. I'm tired of constantly failing, The school grades I had pulled up are now going back down, I'm falling into depression again, and life is going back to how it was last year before I learned about NoFap. I desperately need help, I don't know how to fix this... PLEASE HELP!