Not to beat a dead horse, but if a wife googles CDing and hits upon one of the threads here about "preferring vaginas or breasts", or "how many of you would transition if you could", or "how much do you think about the CDing", or even the sexual fantasies, she can get entirely the wrong impression.
Even if she doesn't read this in TG forums, people in general base their opinions on stereotypes seen in movies, or news bits here and there, and also images of Drag Queens. Admittedly, there are more TSs than CDS who are in the news fighting for their rights to keep their jobs after transition, or this politician or that model used to be a man and this might be why people who are not familiar with the TG community loosely believe that men who wear dresses either want to become women, or they are gay. These are usually the first questions asked when husbands tell their wives. I used to think this myself before I met someone who crossdresses, and I had to take the time to learn otherwise by participating here.
It's just a learning process that anyone needs to go through once they have a TG in their lives and this can only be accomplished with lots and lots of communication, and also evidence that the husband isn't going anywhere even if he does CD.