What is the interpretation of seeing light in a dream, and does it offer a cure for prolonged depression, despite consistent worship and attempts to seek healing?

Allah knows the reality of this light. [The questioner] is advised to seek refuge in Allah, strive diligently in supplication (Du'a) and remembrance (Dhikr), recite frequently the supplications for distress, send blessings upon the Prophet (peace and blessings be upon him), and exercise patience and seek reward from Allah during affliction, while continuing to consult trustworthy doctors.