Guess I have to say I like the story ... pretty real, in the sense that stuffs like this, affairs, do happen. And strange enough, many are discovered despite the many smart attempts to hide.
But I should have read it before reading the comments. I got a bit influenced, and so went in trying to see if there was really too much stress on technology.

In the end, I think its still pretty alright, though I did feel that the references to google and yahoo was feelt pretty much like "product placement" ads.
The line "They got subpoenas from wimax providers, google, yahoo, ISPs. " was to me abit awkward. "Wimax providers" and "ISPs" are generic terms for any service providers while google ad yahoo are specific service providers, and even "Wimax providers" itself is a specific type of "ISP". The 'sudden' mix of these two groups made it feel awkward and unnatural.
Perhaps if it read "They got subpoenas from ISPs, search corporations, credit registrars" would still highlight the implications of today's information connectedness without feeling contrived.
But after that line, the story pretty much spoke for itself and felt like a good read.
oh, and I also agree with tribble on making it a multiple post. Would make it more realistic.
Say, start off with a post on her being worried about her husband. Followed by a post on the results. Then some uneventful posts. Followed by one of her fear that her hubby getting the email. And perhaps couple more ramblings about her fears. A last post could sum it up after a certain unannounced absence, apologizing for it and sharing her thoughts and her hubby's final email to her.