Girls, would I offend my girlfrend if i told her I think she looks y smoking a cigarette, I am ashamed?

I have always been opposed to smoking since non of my family members of me ever smoked cigarettes or even tried them....but, the problem is I am now dating a girl who smokes...I thought she wasa cute the first time I ever saw her, but when I found out she smoked cigarettes I refused to go out with her even tho she begged me to....she chased me around till I finally agreed to date her and now I am really in love with her....I think I have some kind of or something toward her smoking....this is weird but I really get turned on by the way she holds her lit cigarette and exhales the smoke....when whe is smoking a cigarette and wearing a really y outfit like skin tight jeans I go over the edge...I would like to tell her but I am afraid...also I think she might be offended, but I am afraid she will find out or that she already knows...what should I do