I think perhaps my personal dislike of this (ignoring the misogyny for a minute) is the drawing-in of other people to the 'drama' so that they become unwittingly complicit in the 'relationship'. It speaks volumes to me that it's unheard of for single people to claim work-wife/work-husband status, because there is no need for it. Why is there that need for people who are married? It sounds dodgy because it is.
I was reminded earlier of my first job in the typing pool in the local council; I was 18. My first day meeting my new colleagues, trying to remember names and being told categorically by 'Linda' to remember at all times that 'Nigel' next door was her work-husband and that any messages taken for him should be given to her to deliver. What did I care? I was more concerned about finding my way around the huge, old building.
As the weeks progressed, 'Nigel' used to come into the office a lot. I was the youngest by about 20 years and perhaps that was the draw. I had no interest but 'Linda' would cold-shoulder me and remind me of her 'status' as office-wife, getting approval and back-up from others in the team.
'Nigel's' real life wife popped in at one point, I think she'd worked there previously. Naively I was expecting real-wife and work-wife to be pally since they had 'Nigel' in common but work-wife went very, very quiet and 'Nigel' blanked her.
The penny dropped and I saw it for what it was. Just two silly people, one of them utterly deluded and needing therefore to make it real by involving other people. Not so different from an OW at all.
The point is, if this is innocent and there is no sexual frisson at all, then really, what's the point in making out that the relationship is one of anything other than colleague with friendship? I think some posters are being incredibly disingenuous and, as with OW who feel pilloried on being questioned, work-wives will just join them, underground.
It's all a bit silly and nobody's really fooled. It is bloody annoying though being co-opted into the fakery and I want no part of it.