It's a very natural discussion, one that we had under similar circumstances (actually, we'd just fucked and were waiting for me to get hard again). We were both single and we both had an ex. To me, it has always seemed like once married, it's much easier to have sincere and honest conversations about likes, dislikes, fantasies, fetishes, etc. etc. It was on our first date that my wife gave me some not so subtle hints that she was up for more than just a traditional married sex life. Although we were just having our first date, by the end of it I knew that she was having sex with 4 other guys, and had been for some time.