Hannie, I tend to agree with you, but somehow, looking at (please no offense) some of the baggage accompanying expat males, I can imagine why they (the baggage) suspect their husbands and distrust the "tiny Asian female" after they have had a few kids and let themselves go to pot while trying to raise the family, not realizing that they could have done both. (I know that sounds chauvinistic as well - not meant to be). The males, on the other hand, may well have let themselves go as well, or not, as the case may be, but if they still had any spark left between them, then the male wouldn't be quite so easily swayed. It's usually a cause & effect type of thing. Subtle, but over time and with the right temptation, fatal.
The old expat / young Asian girl isn't as prevalent as it used to be, like when I first arrived here in 1982. There was still a lot of that. Now, the average age of most expats is a good 20 years younger and they are still reasonably fit and if married, tend to stay that way, but if single are a good catch by some Asian standards (definitely not all). For the record, as noted previously, I'll be married 30 years this year. My "Yellow" fever wife is neither yellow nor 20 years younger than I. In fact, she's 14 months older than I am. I have been married previously, but was single/divorced well before coming to Singapore.
x9200, then what you are saying is the age spread isn't much difference that what is normally found in the west as well. (Unless it was a case of marrying your high school/college sweetheart where the age, even then, could still vary by four years (e.g., freshman married a senior college student). But I believe Hannie is talking about the middle-aged expat with a mid-life identity crises.