Sooo....my mom still wont lemme lock the bathroom door!?

K so I had this problem before. My mother wont let me lock the bathroom door. She walks in on me without knocking to drop stuff off. Its so annoying. Really, what else could I be doing besides using the bathroom? Just because everyone in my family and all my friends do drugs does not mean I do them. They mess you up! Its stupid. I am 14, and I feel really awkward when this happens. No one gives me privacy. Heck Ive seen my dad trying to read my diaries. I know I sound like a normal teenager, but there is more to me than I can let anyone know. WAY MORE. As in life ending, world shattering stuff. And thats not an exaggeration. Im not sure what to do anymore. Im home schooled, so no school counselor for me. I also dont have someone I can talk to. Besides my bestfriend. What could does that do? She has the same problem at her house with her dad and "step-mom" (they arent married yet). Talking to my boyfriend might work, cause my mom loves him. My dad doesnt know about him. Cause hes 19. I know what youre gonna say "Hes using you, blah blah blah" and youre going to expect me to not listen. But heres the thing. He understands me better than my bestfriend of 12 years, and Ive only known him for 3 weeks. My bestfriends a normal teen. My boyfriend and I truely are not. We are.....very very much different. You shall find out in the future years to come. Anyways. Back to this problem of mine. The bathroom thing. Help? (Figures I can make the wind blow, and the Earth to shake, literally, but I cant make my mother stop bugging me. This sucks)