I have serious trouble not hating people who use them. It's because I know where the long road ends, and it's not a good place. I don't believe in people's ability to control themselves once drugs/alcohol enter the equation, and thus, those who do use them, are (in my mind) irresponsible and looking to hurt everyone around them.

I get that you're coming from your personal experience, and with your personal experience your viewpoint is understandable. However, it still remains black and white, with nary a shade of gray. I do believe there is a place where one can drink, and even smoke a bit of weed from time to time, without being completely irresponsible and ruining a life.

Not everyone who eats a slice of cake from time to time becomes obese. Not everyone who has a drink from time to time becomes an alcoholic or hurts those around them. Even the people who sometimes overindulge all night (party! let's eat cake, onion dip, AND damn those appetizers look great!) don't have to end up "at the end of the road."