Am I a horrible person for feeling as i do about my ex wife?

She and I were not close, but I thought this was normal. We lived in the same house and we had sex, good sex. But there have been many times over the last 25 years I have thought of her. once a day some time and then a few times per week. I guess its the good times, not the bed times and problems that ended out marriage.
We had sex that lasted all day long many times, Yet I get better satisfaction from an hour of sex with my wife today. I still liked the massive work out she gave me in bed, and watching her get sore from the time we spent drilling in and out of her.

We had some memorable sex that are some of the best of my life. Pure physical as we had no passion, I had the feeling I was with a paid hooker most of the time. I guess I am a person who now and then could go back and be with her like she was a hooker. I doubt that is an option, and i would NOT wager loss of my wife I have today for that feeling. My wife today and i have great sex with a lot of passion. I know she loves me and what i do to and and for her. She does the same for me as well. I do love my wife and would lay down and die to keep her a live.

I just wonder had i given it more work, if I had been a better husband by talking wit her more. I just know i work my ass off to keep my wife happy, and I want to let her know daily that she know i do so.