Thanks, karen. I HAVE told this to MsHdog, many times, in many ways. Her answer has been, pretty consistently, that the fallacy in the "sex is the foundation that defines marriage from friendship" is that my definition of "marriage" is too limited.
Which is fine, for her. I just wish that she had let me know this before we got married. Perhaps I should have asked her the question about sex and marriage before we got married, but it didn't occur to me at the time.