I mean, speaking for myself, I don't know that I could marry someone who was previously divorced (whether in the legal cultural sense of the word, or simply being separated from her first husband whom she slept with). Not that I think it shouldn't be done, but it is something I know I myself would not be able to do, short of a miraculous intervention from the Holy Spirit. Which He may very well do... perhaps as I write this He is laughing at me and planning to bring a former prostitute along and ask me to take her as my wife! But not unless He REALLY clearly directs me. But for you, Philip, I can only applaud you and admire your strength. Clearly God made you with that capability and brought your wife to you knowing that you would be able to guide and cherish her and forgive her past (I think that's what I'm reading from your message, forgive me if I am assuming something you did not mean!). God bless you! I wish I had your strength.
But perhaps that passage is written for someone like me, who would surely struggle greatly with the idea.
And yeah, I would only marry someone who had that dedication to me and me alone. I would only pursue someone if it was for potential marriage, and I would only seek potential marriage with someone who was devoted to only me.
And you mention not having scriptural backing for that, but I think Christ asks that of us all over scripture...