It could be the case for a lot of depressions. Depression isn't a single illness but many which is why anti-depressants have a baseline success of 1% over placebo. You have to discover what it is your body needs or lacks. One doctor has described it that headache isn't caused by an aspirin deficiency.Wow, ok. I'm asking that question for this reason: I'm still not fully convinced that depression is a "real" illness. Not real as in it doesn't exist, but real as in it can be cured without drugs. I think it's more of a mood problem influenced by other aspects in your life. For example, when I was younger and very poor I often felt despondent or maybe depressed. Days or weeks would go by where I couldn't feel happy. I used drugs and drank a lot and that made me feel better. Eventually I got out of the mentality and grew as a person and in business, I moved to the US, I made something of myself. I then stopped using drugs completely a few years ago and I don't drink nearly as much. Like I said, smoking quit cold turkey as well. So maybe, it may be worth considering trying to get better without taking the prescription drugs and getting addicted to them. Again, I might be way out of my depth here.
The focus on SSRI's seems to have been the wrong treatment based on an incorrect theory that depression is caused by a serotonin deficiency. It actually seems that depression is caused by brain damage resulting from or not resulting from serotonin deficiency. Treating it with SSRI's therefor will help as more serotonin makes you feel better but they don't treat the problem. On the other hand there are people with below normal serotonin and no depression or normal serotonin and depression so that also seems like only one of many causes.
Magnesium has been found effective in 50% of cases of treatment resistant depression. Not enough sun is a cause of seasonal affective disorder. Some people respond to dopamine reuptake inhibitors instead of serotonin. If there's brain damage then none of these will have a complete effect though but there are some neuro growth factors like GABA that can help regenerate neurons.