It sounds like you have a great dad who loves you very much. However, you two obviously have very different views concerning cannabis. You and I both know the truth, it seems your father doesn't and likes his sobriety. You're not too young, that arguement is frankly absurd. I would move out asap. If smoking cannabis makes you happy, then continue to do just that and feel no shame what so ever. For me freedom is more important then comfort, you sound like you're in a pretty comfortable situation, homewise, at the moment. It's up to you, you can respect your father and honour him, by obeying his commands. Or you can do the exact same, but stand up for your beliefs and values. A true loving father would not disown or kick out his son or daughter for consuming cannabis. Get out and be you is what I say.