To the guy who is worried because his wife was looking for her anklet:
If you don't have any other reason to doubt your marriage, don't waste any time worrying about it. Its a common enough bit of jewelry and doesn't mean much. Dressing up for girls night out is also common. Without any other context, they don't mean anything. Unlike men, women often plan what they're going to wear for an occaision days earlier, rather than 20 minutes before they leave. That she would then search for the anklet to complete her mental picture of herself for the occaision isn't peculiar or sinister.
Its always more likely that a woman interested in enhancing her social status on a given occaision will be influencing others by wearing nicer clothes, jewelry, perfume, eye makeup, etc. That applies just as much to women out with their friends for a girls night out as any other time. Women generally don't dress down for each other, they dress up. Men are more apt to dress down for a night out with the guys. (Women dress up to signal the social status they would like others to think they have, at the risk of being competitive with each other. Men dress down to signal that they are not competing with each other for anything, at the risk of being underestimated.)
Unless something else about your marriage would have you believe your wife has transferred her affection to someone else, there was nothing to it. If your sex life stopped 2 years ago she's out 7 nights a week and returns just in time to dress for work, then the anklet wasn't the clue you should have been paying attention to anyway.
And as for the rest of the jewelry salesmen out there peddling the hot wife theory... You're more likely to sell fewer ankle bracelets this way rather than more. In my area, just about any woman whose weight is under control enough to merit baring her ankle wears an ankle chain, and it doesn't signal anything. They don't last all that well so they buy a new one every few years. If they thought if signaled something, sales would evaporate.