You say that because Matthew was preaching the reign of God, Jesus did not intend to be taken literally on divorce.  That's a complete non sequitur.  I don't deny that Matthew was exhorting us to different way of thinking.  How does that mean we must take Jesus as meaning something other than his plain words tell us.  

You are the one who said that we can't take Jesus literally because it constitutes line-drawing, which we mustn't do.  But with his statement on divorce, Jesus did exactly that, because line-drawing is what one does when he passes an edict or a commandment.  You draw a line between what is permissible and what is not permissible.  Jesus did that.  You disagree with THAT?

You say:  "So I put this question: what commandment do you follow when "love of God and neighbor" conflicts with "let no man put asunder"? 

You follow the commandment, because to follow it is to love God.  Following a God-given commandment never entails not loving God.