I've smoked Marijuana in my day, thankfully I have never become addicted to it. I do know some people who seem to need it. Someone I know on a personal level actually smokes quite a bit, almost every single day, and gets overly crabby if she doesn't get to smoke. Addiction can occur if one becomes dependent upon on it. Marijuana has been known to help with depression, anxiety (also heightens it for some) and other medical conditions. But sometimes taking so much means it's less useful and therefore some people need to smoke more. Anyways, just remember, that even Marijuana can be addictive.