Its hard to give something up that is so fun but what your parents do for you and who they are is way more important than gods plant but its your decision i was in the same situation you are except my parents made me a deal either they would buy the weed i had left cause they found out that i smoke or i could smoke the rest of it and just not buy it ever again i chose to smoke it cause i will miss it very deeply but over the time they have not seen me smoke but they have realize i act no different and they allow me to make my own decisions since i showed them that people who smoke pot dont act completely off the wall