[Objective]

''I smoke responsible.''

This does it for me, tell her that it's one of the things you enjoy and that it ups the value of your life. Not that you can't without it, but it's much better with and that's reason enough for you not to quit. Since she's your wife shit's pretty serious and you got to figure out what to do, but if it was a gf of mine or whatever I'd tell her that I'd feel bad that someone I love so much and enjoy spending time with would be in the way of something that makes me feel good every once in a while.