In Recipients, found one other reference for my wife (other home networked Mac user name, same email address as mine). BUT it was for an old server account with an obsolete e-mail address, not used in years. Deleted it.
In the address books on both computers, both networked users (Myself and my Wife) have listings, BUT each is correctly and respectivelly listed as the "Me" person. Also, there is an additional duplicate for my wife, but for the purpose of uploading to my cell phone directory, but without an email address, only a phone number. And lot's of these for others for phone directory purposes.
Sorry to intimidate. Appreciate your help. Just kind of bummed out with Apple. They seem to develop their stuff to a point, and then leave all the outlier defects languish forever. All they need to do is point to the mail account user name instead of whatever complicated thing they are trying to do.
And should the above action somehow help, rest assured I will return to award you a "solved".