well, my bf hates smoking. can't stand the smell at all. but, he loves me and he knew going in that i'm a smoker. i've always said i'd quit when i started having kids--since i won't be doing that, i'm free to smoke till i feel like quitting.
there have been a few bumps in the road regarding my smoking. primarily, he worries about me and wants me to quit because of what smoking does to your health. i'm aware of what smoking does, but i choose not to quit. i'm a big girl and i accept the consequences of what smoking does to my body. he can choose to not like it, but i will not allow him to nag me about it. he knows better than to bring it up--i will quit when i am ready to quit, not when he's ready for it. cheeseburgers aren't healthy for him, but i don't bitch when he eats one
if you want to ask her out, then be prepared to deal with her smoking. and that means accepting she is a smoker. you can negotiate about sitting in non-smoking sections when you go out to eat (she can smoke outside when you are done), you can ask her not to smoke in your car or your home. but she is a smoker, and if you ask her out, do it knowing that you are accepting that part of her too. i promise you, explaining the health risks or why you find it disgusting is not going to make her quit--and bringing it up is only going to piss her off. if you can't tolerate the smoking, don't ask her out.