Don't preasure him to quit, you'll only make him want to do it more. I was that way. It was the little things my wife and family did that made me want to quit more than the nagging and scare tactics. Examples
My wife would go to kiss me and say, "oh sorry you have that shit in your mouth"
I wasn't allowed to leave spit bottles in site where my wife could see them, if she did she threw them away. Use to piss me off, nothing worse than searching for something to spit in.
Every time I spit someone would make a spitting noise, that really aggravated me, don't know why but it did, spit everytime he does. Maybe in the back of my mind I realized how stupid I must look.
Every time I grabbed my tin my wife would always roll her eyes and say "your going to put that shit in your mouth now". Would make me think about it for about 5 mins, I did it anyway but I thought about what I was doing.
My friend would always say "have something in your teeth"
Again if I had a lipper in my wife would always offer me gum, food, anything and would always say "never mind I forgot you put that shit in your mouth"
Thats just an example of the little things that use to make me think more about how stupid I was. Just remember he is not going to quit for anyone other than himself, I wouldn't quit for my wife. If he quits for you I wouldn't beleive him, If he does he's a better man than I. I am only on my 3rd day quit, so by far no expert. I have tried to quit numerous times all for the wrong reasons. This time is different Because I, I, I, (get the picture) want to. I would also tell him how uncool and ridiculous a man looks carrying a bottle around. My entire world revolved around a 20oz bottle. Just like a newborn, I was pathetic. Hope this helps.
Turkey