If you have a bad marriage (your spouse is cheating, abusive, you just don't love each other anymore) you should be able to divorce them and marry someone else or stay single, if you prefer. My uncle's wife cheated on him. Should he have been forced to remain married to her, knowing she loved someone else?
If two people who have been married both agree that their relationship is not work saving, then they should be able to get divorced. It can be a peaceful end to a bad relationship. It can also provide a better environment for children. Parents can remarry, and kids do not need to see their parents fighting all the time.
Besides that, who is? What child would say that they'd just love to have their parents divorced? I can understand that it might be a wise decision when two adults decide to marry for foolish, slapdash reasons, and then go on with their life making others miserable with their constant bickering, but I don't think married adults should divorce just because both of them refuse to face their problems and the troubles with their marriage. Marriage doesn't flow beautifully from the start, it's built up over time, and only gets better and stronger with age.