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I would suggest that both of you start at her initial psychiatrist and therapist appointment. The psychiatrist will give her an evaluation and start her on medications if needed. The therapist will help her work through what is causing the depression and how to best deal with it. Many of her appointments will be just her working through this but if you attend the initial meetings they will be able to work out a schedual where you will both be able to attend some of the appointments.
I hope this helps. Let me know if I can help anymore!