Normal
I don't think they're either or, but most probably both. There's situational depression that can be triggered through life changing events. Developmental issues also come into play, because for instance Autism is a spectrum, you could be the slightest bit autistic and that could potentially affect your ability to integrate in your environment. Then there's hormonal imbalances like childbirth, hair loss, erectile dysfunction and so much more.There's no one size fits all sadly and everyone has/could have enough of a biological and environmental combination to become mentally ill (which in itself is too broad of a term).
I don't think they're either or, but most probably both. There's situational depression that can be triggered through life changing events. Developmental issues also come into play, because for instance Autism is a spectrum, you could be the slightest bit autistic and that could potentially affect your ability to integrate in your environment. Then there's hormonal imbalances like childbirth, hair loss, erectile dysfunction and so much more.
There's no one size fits all sadly and everyone has/could have enough of a biological and environmental combination to become mentally ill (which in itself is too broad of a term).