Your arguement, and the entire premise of the thread, is based on female prostitution. I accept that any other form is the exception, not the rule; but we must view the arguement in non-gender terms. Legalizing prostitution implicity includes male prostitution, so trying to base a response on the opinion of 'wives' is a bit ludicrous. It also ignores the reality of customer/clients who are not in a relationship - ie, single.
Far better that the argument and the point be made in the abrstract - enough people will object to legalization without trying to specify wives/spouses as a sub-set of opposition. For my own perspective, the question legalization is being addressed in reverse. Proponents should not be looking for reasons to legalize; rather, they shold be arguing that there is insufficient reason to make it illegal. In a free democracy, the onus should be on government to substantiate reasons to outlaw an activity; not to legalize one. For myself, I find the current arguments against prositituion to be insufficient.