The expensive people are those who, because they are not simple, make complicated demands--people to whom we cannot respond spontaneously and simply, without anxiety. They need not be abnormal to exact these complicated responses; it is enough that they should be untruthful or touchy or hypersensitive or that they have an exaggerated idea of their own importance or that they have a pose--one which may have become second nature but is not what they really are.
With all such people we are bound to experience a little hitch in our response. In time, our relationship with them becomes unreal.
If we have to consider every word or act in their company, in case it hurts their feelings or offends their dignity, or to act up to them in order to support their pose, we become strained by their society. They are costing us dearly in psychological energy.