Gents,
Perhaps it is not all physical this "sex drive thing."
One of my buddies was 38 when he noticed a marked decline in his sex drive. He went to a urologist and was given a clean bill of health (normal test level). When they were going over the results of his blood tests and the Dr was assuring him he was ok he told him, "you just gotta find the right duck."
As we get older we become more set in our ways and our TASTES. What we found attractive at 25 we might not find attractive at 35....I like "spinners" when I was younger but now I prefer an hourglass figure. One man's stunner is another man's reject.
Just a thought......