I identify with your tale about smoking. Both my parents smoked when I was young. I was never going to smoke either. Then I met my husband and he smoked. I didn't for some time, but I succumbed after he tried to quit (for a day) and couldn't. I knew I'd hound him all the time, so if you can't beat 'em, join 'em.
Not a good choice for me. He still smokes. I still smoke after 32 years but I've had times when I didn't and I enjoyed them.
A lot has changed in 32 years in the public view about smoking. My dad died of lung cancer 13 years ago. I have two daughters, 24 and 28, and they both smoke. The older has already been told she's at high risk for emphysema. I'm having issues from smoking. My husband happily puffs away.
Your daughter is an adult, and she's getting ready to marry and move out. Remember the Crosby, Stills, and Nash song "Teach your Children Well"?
The teen years were tough on me. Now that they're in their 20's they've told me some of what they did in their younger days, which I was mercifully spared from knowing at the time.
Chantix is a good prescription product to quit smoking. I tried it and it worked well, but I didn't follow through with refilling it for the second month. (It's around $130/mo.) I should have because I had quit and it removed the desire to smoke.
We all know the hazards of smoking these days and smokers have almost had to go underground. If you hound her about it, you're just another one of the pack of hounds. It's ultimately her choice and she'll make the right one eventually. Don't drive a wedge into your relationship over this issue. Please.