I do not necesarily agree with how it is a real bodily thing. The Metropolitan Behavioral Health of the US has specifically said after research "While neurotransmitters like dopamine, serotonin, and norepinephrine help regulate mood, energy, and pleasure, research shows no consistent evidence that people with depression simply lack or misproduce these substances", clearly showing that depression is not caused by a literal imbalance of the neurotransmitters. Also, me saying that social causes or personal habits can be linked does not have to mean I accuse them of 'a personal failing'. It does not mean it is their fault, if I have a bad depression because for example a family member died or because I've been fired from an abusive job, it is by no means my personal failure or something I could have controlled. And by stating that certain actions could have been taken, like mental exercises or others in order to HELP the person does not mean I am saying it's their mistake and that they deserve to be in a depression. The fact that we acknowledge that some of them could have been prevented does not mean we think less of the person or that we do not want to help them, if someone got to the hospital because they have been playing with a chainsaw doesn't mean we don't treat them, but it still allows us to advise them to not do it further, for their OWN good so that it doesn't repeat.