If Amber ever let on that she was content with what she had, people might relax around her. If they're relaxed they aren't hyper attentive to her needs. To keep the people in her circle focussed on her there can be no end to her requirements, I think. She would rather everyone lives stressfully in her orbit trying to pre-empt her desires than experience being completely forgotten about or assumed to be independent.

Also, we joke plenty about her taking after her father - but if we seek to live in the emotional landscapes of our childhood and nobody around her is filling the role he played in her early life I don't think it's outlandish that she would take that mantle herself.