Damn... thats kinda how i felt about a year ago.
Then i lost a parent and gained some wisdom and shit on the matter. Basically, it was gonna be a conflict between me and moms, and i just straight up told her that im gonna smoke bud and that theres nothing she can really do to stop me, short of sending me to rehab. I made sure it wasnt a huge issue and it kinda died down, she was still disappointed but she backed off about it, we laid some ground rules and now its basically i just gotta stay responsible and active and do my thing and if bud doesnt affect that it is a non issue. TALK TO THEM... NO MORE FUCK YOU THIS FUCK YOU THAT... you need to be a man and straight up tell them that you get your shit done (if you do, of course) and you are a stand up guy basically and say that if they wanna stop you from tokin up, that theyre gonna have to send you to rehab.
Maybe youre not as crazy as me though, if she had actually sent me to rehab, i probably would have ran off and joined the circus...