Parents are guilty for their children's psychological problems after a divorce. When parents divorce, it literally rips a child in half. You have to go to one parent's house one weekend, the other parent's the next, etc. It's very emotionally draining on a child, and that some times leads to problems.
When one has children with another, they should set aside their own personal interests in other people, or lack thereof in their spouse. Their number one priority should be to be happy with their spouse. If they just can't make it happen, but they tried everything they could, then they should at least stay together on paper. In other words, fake it until you make it. Children are the most precious of all people and should come first always.