Second night of Divorce Recovery Course: 
What stops us communicating well?
Fear, Fear of verbal retaliation, Fear of physical retaliation, medication/ substance abuse, dishonesty, lies, "emotional unavailability", Not articulate enough, broken trust in past, boundary-less discussions in past, financial pressures, unhealthy intrusions from in-laws or friends, fear of vunerability, sulks and silences, revenge?, radically differing views, judging and critical, confusion with new situation, Anger, outside pressure.
These are a few of the issues that came up, no wonder communication can be so difficult if some of this is going on underneath! Just seeing this list helps me acknowledge issues that might be going on for myself and the other person.