I see attractive women all the time while in the presence of my significant other, but I'd never disrespectful her by saying anything or bluntly highlighting another woman's beauty.
My wife knows I'm not dead or blind, but I never take it there.
Just like I see women in passing that I occasionally find attractive, I'm sure she sees men in passing that she finds attractive.
She's human just like I am; however, keep those comments and overtly trying to bring attention to it to yourself. That's when the innocent physical attraction turns disrespectful when you chose to make comments.