The Women - 4:35
If you fear that the married couple may fall out, you should appoint an arbitrator from the man´s family and an arbitrator from the woman´s family. If they wish to reconcile, Allah will reconcile them. Allah is All-Knowing, All-Knower.
Related:
The Women/4:128
If a woman fears that her husband is unchaste or that he will turn away from her, there is no harm in their reconciling their differences through reconciliation. Reconciliation is better. A person tends to be selfish and jealous. If you do good and act virtuously, surely Allah is aware of what you do.