Despite the sanctity of marriage, the Torah does provide for the possibility of divorce; in truly serious cases of dysfunction, it is even a mitzva. This is because the purpose of marriage is for the couple to live together lovingly, happily, and peacefully. When there is fighting and suffering instead, divorce is permitted. However, couples should invest every effort in saving their marriage.
Anyone considering divorce should be made aware of a few things. First, many of those who initiate divorce realize years later that they made a mistake. While fighting with their spouse, they were sure their lives would take a turn for the better after divorce, but the problems and frustrations actually stayed with them. Second, even in a second marriage, a relationship will run into trouble unless there is generosity of spirit, an investment in the relationship, and a willingness to yield. Perhaps if they had adopted these attitudes in the first marriage, they could have had a happy marriage. Third, divorce is generally hard on children. Therefore, if at all possible, a couple in crisis should do all in their power to repair the relationship.