I suppose it all depends on how much of this you can take. Different people need different time to get over a death like this. Some take 3 months, some take 3 years. So it really depends on you and how much of her sadness you can tolerate.
Counseling for her is a good start. Maybe after she has been to 5 or 10 sessions, ask if you can go with her so you can understand her position. The danger I see here is she may be overly focused on the negative of his death, instead of the positive of his memories. People sometimes get in a "rut" and never come out of it for years and years. This is bad for you because it is unlikely you will get her full attention, and unlikely you would get your needs met.
Both people in a relationship have to have their needs met, and if one is preoccupied with something, then things often don't work out.
I have a long time interest in psychology, specializing in relationship dynamics for 30 years.
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