Not as easy as it is to say, but "I'm sorry" goes a long way when you mean it, even if you don't understand what's wrong. If I'm sorry can break some ice, a quiet heart to heart talk without any type of blame or arguement can most times reveal problems. Let her talk when she talks and be careful of what you will say. After you have gotten to the root of the problem, you can progress. Like we say, not easy to do as it is to say, but we hope to have helped in some way.