The important thing is you want jesus in your life. Keep trying and you will defeat all of these chains!!
I am a 22 yr old woman. I to have strugled with drugs and alcahol. From my experience its one thing at a time.. dedicate yourself to geting one of those things out of your life and pray you will no longer be temted by it. Ask yourself why you feel the need to escape by using these things. And know that jesus is the only true happiness and escape from the world anyone can have. Its really hard i still struggle. But you get better at saying no! God will deliver you from this if you want him to. Find strength in our fathers love by reading the bible and praying. You are so loved by God and jesus!
God bless and strenghthen you!