Well, I ve been married 35 years this January. When I got married I was 145lbs, she was 110lbs.
Today is a different story. I'm 215, a bit larger that when I was younger but, I'm pretty solid, I work out a lot. My wife is about 160 and she always is fretting about her weight. I don't really care about it because she is my friend and lover. I'm a flirt too. I like looking at pretty women but, I don't do any kind of porn. Pictures of women I know I'll never have don't do a thing for me. I'm a man of action. I like interacting with live people. A movie or picture can't love you back and self gratification is for young boys. Why waste what little time I have left here on earth in fantasyland.
as far as not being in love, well it goes in ebbs and tides. Sometimes it's overwhelming and sometimes it is not even there but commitment is what should keep it together.
My wife and I have been through so much that to pick up and leave is out of the question. Reflect on your life and remember what brought you together in the first place, if it was just good looks and sex then there isn't much for that relationship to thrive on.
Wanting something different is not wrong. Throwing away a lifetime friend is.