While a patient is in depression, the world is dark and lonely. It is very very difficult to reach out to the sufferer. They need professional help during the treatment.
The treatment usually consists of psychotherapy by a trained clinical psychologist and medications given by a family doctor with interest in mental health or a psychiatrist. Failing which, they might even need admission under the care of a psychiatrist and his/her team in a hospital.
Even though it might sound like there is no role for the family to play, the biggest deciding factor for whether patients will actually recover is actually "strong social support". What we mean is that, patients who have family members or friends who are supportive of them through the treatment period are more likely to reach recovery.
So family members and friends are absolutely core to the recovery of depression sufferers. Usually what they have to do is nothing. And just be there for them.
You really don't have to do something extraordinary and you can't anyway. "You can lead a horse to water, but you can't make him drink". The patient will have to walk out him/herself, but with the close support of family and friends.
For further information, you really should check with the team who is caring for the patient.
