Thanks Penguin,
Pot is really an under-discussed addiction.
My oldest A bro gave up drinking in his 20's but smokes pot 24/7/365.
I have a very distant relationship with him. And now his youngest son is smoking (16) and failing high school. And he and his wife wonder why I don't visit them for vacations (they do live in a beautiful part of the country) but honestly, I don't want my kids around that. Plus he's either a Grumpy Gus because he hasn't smoked yet in the a.m. or he's spaced out and in his own world when stoned. No thank you!
The last time he came to Boston years ago w/ his wife and 2 boys for a family reunion he sat on my front stoop and lit up a joint. I went downstairs and said "Uh, no!" So he walked a half block away to a schoolyard to smoke. Nice. He didn't even realize a police station is right behind the school.
It has its hallmark side-effects, but like alcohol or any addiction it is unhealthy and gets in the way of real life! So I choose to stay away from him and his "lifestyle!"
I have learned my lesson and will never involved myself with somebody like that again. 
I salute you & I know how painful it is to have to say goodbye to a wonderful person who is an addict. But it is "let go or be dragged!"
Peace-
B