He might have overslept, or maybe he got stuck in traffic. Assuming the worst puts a huge stumbling block in the communication process. So does speaking in absolutes. Absolutes put the other person on the defensive, and it becomes hard to communicate when you are busy defending yourself. Another barrier to communication is making assumptions and placing blame.
Some people think there is money where there really is none.
His ex has no idea that he was actually driving his boss's car. Her family is wealthy. Her family isn't responsible for the children. The children's two parents are. Many of these misunderstandings don't arise from one person trying to destroy the other.