Question Summary:
What duas and advice can I offer a friend suffering from severe depression?

Question Detail:

I have a close friend who experienced a traumatic event and they have subsequently, fallen into depression after years of suppressing their emotions. They are struggling to open up to anybody about this and nobody else has an idea about this except me. They are studying to become an Islamic scholar, therefore their iman has not been lost, however due to this experience, they are having suicidal thoughts and they constantly feel like self-harming. I am deeply concerned for them, so please can you provide me with some du'aas or surahs for them to pray. Any additional advice/tips from you is truly appreciated also.

Answer :

In the Name of Allah, the Most Gracious, the Most Merciful.
As-salāmu ‘alaykum wa-rahmatullāhi wa-barakātuh.
Respected brother,
In the situation that you describe, we recommend that as a close friend you try to make your friend open up to you and confide in you his feelings and thoughts. Suppressing his feelings can only make his depression worse. In doing so, try to impress on him that he needs to seek professional therapy and help. He should do this by seeing his doctor who will be able to advise him on the best treatment options and refer him to professional therapists. You may also recommend that he visits a trusted imam or ‘alim who is known to deal with such situations.
You may recommend the following du‘ā to your friend:
لَا إِلَهَ إِلَّا أَنتَ سُبْحَانَكَ إِنِّي كُنتُ مِنَ الظَّالِمِينَ 
Transliteration: laa ilaaha illaa anta subhaanaka innee kuntu minazzaalimeen
Translation: “There is none worthy of worship but You. Glory be to You! Verily, I was from the wrongdoers.”
Also suggest to him that he recites the Qur’an frequently. The Qur’an is a shifaa’ (cure) for all types of illnesses.
And Allah Ta‘āla Knows Best
Zameelur Rahman
Student Darul Iftaa
UK
Checked and Approved by,
Mufti Ebrahim Desai.
www.daruliftaa.net