Actually I don't want to have sex with a 25 year old. I really don't. And I do fancy a fair number of blokes my age, 53, which I certainly wouldn't have done at 25.
I'm in my early fifties and I feel exactly the same. It's not that I don't look at some young men and think they are beautiful, I do, in an objective way rather like I might admire a gorgeous painting or dress, or racehorse.
I certainly couldn't imagine leaping into bed or into a relationship with them in a month of Sundays. It just feels wrong. If I were single and a genuine deep connection grew out of a friendship at work or something then I can see how it might happen, when you get to know the person first and the romantic/sexual relationship is something secondary that grows organically. But the idea that I might actually invite or encourage a total stranger with a 20 year age gap to date me through OND or chat to me online with a view to getting romantic, or approaching them and chatting them up in a bar or whatever just creeps me out.
I know a couple who married recently who have been together since he was 25 and she was 41. They did become genuine friends first, they worked very closely together and got on like a house on fire.
When her marriage broke up and she was at absolute rock bottom he told her how fantastic she was and how any man would be lucky to have her. Over a period of months it just blossomed into love. She was a bit freaked out by it at first but then she thought 'What the hell? Just allow yourself to be happy.'
They've been together ten years and married quite recently. But I think at 25 he was a fully formed adult who probably had a fair few relationships behind him and knew what he was doing. And they already knew one another very well before it became a relationship.
And there is a big difference in maturity and life experience between 20 and 25 for most people.