I married my college sweetheart back in my mid twenties. The sex went downhill almost immediately after marriage because she was not satisfied with the state of my career and our standard of living back then. It's so hard to enjoy sex with a person who feels more like your boss than a lover.
Anyway, I manned up and divorced her. Then I had a 20 year old GF when I was 32. Sexiest girl I've ever met, I lost count of how often I fucked her but I remember the record was 6 shots in a single day. Needless to say, zero punting for years after I meet her.
Then I think after 4 years or so, it started to go downhill. I started to punt again. Why? I guess variety, plus when you punt, you get to fuck a girl who has prepared herself to look hot even when you're having sex. With the partner, she's usually without makeup, ready for bed, etc.