Native Israel said above:
parents have got to mix out of their childrens lives and give them independence
I know someone who, if not for their parents involvement, would be married to a partner who defiantly was not right. Lets just say that, in marriage, one is not supposed to be a mother but a wife (or vice-versa).
You are right, parents have to back off and let the new couple build a home of shalom and happiness. But someone also has to be watching. From afar. And if something comes up, let them work it out. But up to a point.