I have had depression on and off in my life as have manic depression as part of my Bi Polar, I was 15 when I had my first bout brought on by exam stress, the doctor asked me if I wanted medication, I declined and said I just wanted someone to talk to, he then arranged for me to see him once a month to talk about my struggles, he was a new young doctor, still remember his name Dr Trainer, he was Scottish and lovely. Then later on I did end up on medication in my twenties on and off for years and had suicide ideation too, but on the whole all my depression was linked to life events, like my 28-year relationship ending, me being in debt, etc.., diabetes did cause me a momentary downward spiral but since taking control of it I feel mainly very good again. The trouble is when I feel good, I still do silly things like spend too much money etc...(Bi Polar behaviour) - I am not on medication for Bi-Polar as when diagnosed the Psychiatrist told me to diagnose me could ruin my life/career etc, but again we are going back a few years and part of me thinks I have a version of ADHD rather than Bi Polar, the symptoms overlap and as I say the depressions all have a cause. My sister said to me once, I don't know how you are still alive after going through what you have been through (lots of things I haven't shared on here as some of it relates to other people so feel it's not fair, let's just say someone I was very close to had been arrested for a serious offence, the person later said they made it up to make their boyfriend jealouse, but both me and the person involved discussed killing ourselves if it went to court)
I think depression is a part of a lot of people lives when they feel out of control and hopeless about the future, I hope you start to feel better soon x