Tell him to see a sex therapist.

Maybe it's trying to tell him something. : )

All in the mind

Blah blah blah ... "it's" thinking too much.

It is all in your mind fella. I am sure that there are insecurities about being with someone new. After spending twelve years in a committed relationship, moving into another one can be very uncomfortable. After all, now you have to learn about a new person, and they have to learn about you, likes and dislikes and what-not. Personally, I think people rush to the bedroom far too often. Just because you're attracted to someone, even dating them, does not mean you have to jump into bed with them.

Enjoy the dinner before diving into the dessert.