One of my closest friends from childhood is divorced, and one of my wife's childhood friends has been divorced twice. We've also seen a lot of divorce within the family, including my own parents, so I would say we know our fair share of divorcees.
I don't think marriage is a vow that should be taken lightly or entered into quickly, but unfortunately this happens and then many couples can't reconcile their differences, even with counseling, and in those cases, I think it's better for the family members (especially the children) if the parents divorce. I think it's better for a child to have parents that live in separate households than to have parents that argue all the time.