Physical Attraction verses thoughts in your head

I was sharing some of my thought work with a few girlfriends. One of my friends asked me what to do when you are no longer attracted to your husband and it left me a little stumped. Can physical attraction go into a thought model? I would think whether you are attracted to someone has much more to do with actual physical responses rather than thoughts. However, I know for me personally I tend to follow the stereotypical woman in that how I feel about my husband drives my attraction to him and I likely could relay a significant portion of that on my thoughts about him. That doesn’t seem to be the case with men though where their attractedness appears to be much more physiological than mental. In my friends case, her husband had stopped working out and had gained about 60 pounds where she is very fit and always takes great care of her body. She still loves him she just has no physical desire for him.

Where do you think physical attractiveness sits in the model? Do you think it is different for men verses woman?