I believe that depression can be caused by different things. I don't think that meds should be used to treat every case of depression. I do believe that a person can be naturally depressed due to the way they grew up, if they were bullied, had a bad relationship or series of relationships, etc. It also has to do with your thinking. If you believe you're worthless and nobody loves you then you're making it true yourself. My t told me that's called a self-fufilling prophecy.