Having your daughter see a therapist is a good idea. Personally if she was perscribed medicine for ADD by a doctor especially a therapist than she probably needs it. I am only 19 but am majoring psych with a focus in adolescent therapy I know that my opinion might not be all that valid but in class we did talk about children dealing with divorces/seperations. I would guess that her going back and forth from house to house is adding to her anxiety level. It is not your fault for the way things turn out. In reality if your daughter doesn't want to do her homework there is nothing that can really be done except to investigate why she is not doing it. perhaps she realizes on some level that by not doing well in school she is facilitating conversation between yourself and her father. she may think that by the prescence of this dialogue there is a chance that all of you will live in the same house again. Its not your fault... Please don't blame your self

-Jason