Clinical depression rarely has anything to do with what you've done or events in the outside world.
Psychiatry has settled on treating depression with two strokes, a cocktail which is a chemical antidepressent, and a chemical stabilizer, and they expect you to take these daily and stay on it for the rest of your life. I have no evidence for it, but I assume this is some pharmaceutical company's agenda, to keep you a customer for the rest of your life. While it works, chemicals always have side-effects, and with so much exposure, daily, they are bound to compound, making it more difficult to consume.
Therapy alone can cure depression, it just takes a lot of time and effort. I don't think it is possible talk therapy could ever make things worse, but it just doesn't work fast enough. Still, recommended.
But I have discovered a way to cure depression relatively quickly in two ways.
First, chemically, but without a life sentence. I have discovered a substance that will cure depression overnight, not unlike an aspirin cures a headache. You get headaches, too? How would you feel about being told you need to take a daily medication for the rest of your life to cure it? No, one dose will do. The drug is unregulated, and is available OTC in cough gels. You won't find this in any PDR, but depending on the patient's weight, say for a 160lb. man, 900mg of dextromethorphan will cure depression overnight, and it has been for some time in many clinical studies exploring its potential as a fast acting treatment for treatment-resistant depression. You take the large dose with a pepsid, and go to bed, wake the next day depression free, and its depression-killing effects can last up to a year. It is an old and safe drug, and the lethal overdose is estimated, because it is unknown. Though it is an OTC remedy for cough, dextromethorphan has already been approved for treatment of emotional incontinence, which could be seen as sort of a cousin of depression.
The other cure, chemical free, is sunlight. Light in the eyes regulates mood. Not enough light will eventually cause depression. Too much light will cause mania (as we should have suspected from the exploits of Florida Man). Put enough sunlight in your eyes, it will cure your clinical depression. If daylight is not enough, get an artificial light that is an accurate simulator of natural sunlight, which is probably not LED, due to too much blue light, which also damages the eye and slowly blinds you, but you can't go wrong with halogen. Point it at your eyes. You can even close your eyes, light goes right through the eye lids and is still effective at fighting depression.