Aright summer.. i was bad on weed when i was a kid. Mainly from 14 to 18. Litrally everyday. It sent me phycho a lot.
But i managed quit in the end. And it was hard. But the main thing is you want to quit.
For me to quit was pretty basic, i wanted to go in the army and i had to pass a drugs test. I had 6 month i think to get clean. And i got a calander and crossed each day off as didnt touch it. I lapsed a few times. But i hated the stuff in the end. It stops you doing so many things.
But the other thing that will help is.. i changed my life a round. I had to do oots of running to train for the army and gym work. So you also need something to keep you occupied and stay focused.
The gym is perfect to quit weed. And start eating healthy.
Dont worry if you lapse its apart of recovery and will make you stronger.
But also try other things to keep you occupied. Good luck mate