That genetics do not play a role in a scientifically proven medical condition like depression. Forgive me if I misunderstood the point you were trying to make, but I believe you are arguing that depression is in fact not a medical condition at all but a frame of mind that one can simply grow out of (or that it doesn’t exist at all and I am making it up). The ability to grow out of it may be partially true - it’s been proven that pessimistic individuals that focus on negative events and stimuli are more likely to develop depressive symptoms and need to “retrain” their brains/way of thinking using CBT (Cognitive Behavioral Therapy). But I do not believe that is the entire explanation and it frustrates me when people argue this. I do not mean to seem rude or argumentative but I’ve heard the same statements you’ve made from so many people. That’s why so many people with mental illness/mood disorders are hesitant to speak out because so many people argue against its validity. And I’d like to point out that most (99%) of the people who argue that it’s “all in your head” have never experienced true depression or diagnosed mental illness. But it IS scientifically proven - individuals react differently on a base chemically/hormonal level to the exact same stimuli. PET scans like this one even show a visible difference.
Most experts believe genetics play an undeniable role as well - “Anyone can become depressed, but many experts believe genetics play a role. Having a parent or sibling with depression increases your risk of developing the disorder. Women are twice as likely as men to become depressed.” While the exact cause of depression has yet to be proven, the main theory is that “altered brain structure and chemical function is DIFFERENT. Brain circuits that regulate mood may work less efficiently during depression.” Neurons (nerve cells) in the brain communicating via neurotransmitters actually function less effectively. Even IF we take away all science from this and simply say depression/mental illnesses are not real or that they should not have an effect, I believe that simply voicing this idea is still more harmful than beneficial to the individuals who “believe” they have a mental illness. If someone is literally willing to kill themselves over a “perceived” illness, you at least have to give it some credibility. Again, I apologize if I misunderstood your opinion and blew this out of proportion, it is simply something I am passionate about because I live it every day.
EDIT: mainly I disliked the use of the term "fairy tale."