Dee has always been consumed by herself and her needs. She has always been successful, popular and outgoing. So it is perfectly in her nature to just appear one day home from college. She did that because she wanted something: artifacts that prove her heritage. However, that heritage is the one reason she left for college years ago. She wanted nothing to do with the life that her mother and sister live every day. Dee wanted to make something of herself and to prove to the world that she did it. Along with that is her concern with appearances and names. She just went and changed her name. She didn't ask her family, but she changed it to a strange name to make herself sound more "authentic" like the quilt and the dasher. She only wants those items to show off like art. She has no use for them whatsoever.
Here she is wanting to appear like she appreciates her heritage. Yet, she gives up her true family name for a false one. She wants to take items her family uses every day to show off like art. Yet all of these years she has shunned her true heritage. Her actions here show her true personality--she wants what she wants--when she wants it--with no regard to anyone but herself.