My mental health professional seems to think that I have a genetic predisposition to psychological depression. If this is true, then biology and not past trauma is responsible for my current condition. Can I just forget about forgiving then under this circumstance?
Even if you have a biological predisposition to depression, forgiveness can help with the medication you might be taking. Think through your history of being treated unfairly from childhood to the present. You can do this by consulting the Forgiveness Landscape from my book, The Forgiving Life. If you identify certain people toward whom you still have considerable anger, then it would be good, if you so choose, to forgiven them. See if this aids your recovery from depression.
For additional information, see Why Forgive?