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.
The individual who is simple, who accepts themselves as they are, makes only a minimum demand on others in their relations with them. Their simplicity not only endows their own personality with unique beauty; it is also an act of real love. This is an example of the truth that whatever sanctifies our own soul does, at the same time, benefit everyone who comes into our life.
The Passion of the Infant Christ, p.82, by Caryll Houselander
I read this a few weeks ago, and it stuck in my brain. I keep going back to it. The only thing I will add is that it really is a gift to be simple.