I think overall it's the American men who prefer to marry women who are younger than they are. I think they often think of it as sort of a status symbol or a good boost for their ego if their spouse or SO is younger than they are, especially if by quite a bit. I think it is more a case of the men wanting younger women than the women wanting older men. (After writing this paragraph, I may need to run for cover!)

If I were to be really crass, I'd say many women are looking for sugar daddies (which often means that the men are older than they are), and many men are looking for trophy wives.

I am 8 months older than my ex-husband, but, as I mentioned in another thread, I am 12 years older than my fiance. So far, so good.

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Communication is the key.