When we teach our class to prepare couples for marriage, some of these couples have suggested that we teach a lesson for their parents from this verse.
Many jokes are made about in-laws. Mark Twain said, "Adam was the luckiest man; he had no mother-in-law." Some refer to them as the "outlaws." 
Annie Chapman wrote a book about mother-in-laws learning how to get along with their daughter-in-laws. God is teaching us to leave the family in which we grew up (our family of origin). Then, we form a new family unit when we marry. Following God's direction to leave your family is essential to being able to bond together as a couple for oneness in a long term relationship. If either the husband or the wife hold on to the family of origin, they never really form a new family.
The new family (the husband and wife) is the new priority. The new spouse comes before the mother. father, or siblings in their priorities and loyalty. This transition is difficult for many young people, especially if they have never lived on their own or have they have always relied on their parents for physical, financial, and/or emotional support. However, parents can either make it easier or they can make it even more difficult for their children to leave.
For those left behind (family of origin), they are to release their child to a new family. They are to encourage their child in oneness in their new marriage, not coming between or interfering with the new husband and wife.
We have seen parents who hold onto their children and we have seen the ones who encourage them to be independent. I have seen couples who were in conflict or unhappy early in their marriage. When the child goes to his parents, godly parents send them home and say "work it out." Or when the child complains about his spouse, the parent will defend the spouse rather than taking sides with their own child.
Godly parents will not rescue their married children in marriage conflict or in financial difficulties, but direct them to the Lord.
We have also seen parents that insisted on giving their married children advise whether they want it or not. Sometimes, they have unreasonable expectations on how much time they spend together or what they expect their grown child to do for them. Most in-law conflicts come in the area or advise given/received and in time spent together.
We try to encourage couples not to go to parents or siblings when they have marital difficulties. It is very hard for the parent or sibling to be objective or detached. It also causes emotional distress for them, many times over minor issues. We encourage them to seek an objective third party for advice or guidance.
For the parents left behind - the best thing that you can do for your married children is to pray for them and not interfere with their marriage.
For more information:
Parents - Past and Present
