Is it not true, that Jesus did give one legitimate reason for divorce and remarriage? Adultry?
This seems to be evidenced in the following verse;
Matthew 5:32 But I say unto you, That whosoever shall put away his wife, saving for the cause of fornication, causeth her to commit adultery: and whosoever shall marry her that is divorced committeth adultery.
No other reason is given in the New Testament, save this one and it was given by Christ Himself.