My only friend is leaving me.

My daughter has decided to move to Florida at the end of the month. She still lives at home with me. She is my best friend. My only friend. I am overwhelmed with the sadness of how life will be when she leaves. I don't tell her that but I am. I smile a happy smile for her when she talks about it, but inside I am so sad. She has not only been my friend but my travel buddy, support system, and biggest fan. I don't know what I will do when leaves. I really don't.