Every person with depression is different, and everyone with depression has a unique set of circumstances. Usually, a combination of factors will contribute to your mood. While you often can't pinpoint the cause of the depression, understanding the circumstances can sometimes help you understand how to best manage it. External factors Life events associated with depression include: long-term unemployment living in an abusive or uncaring relationship long-term isolation or loneliness constant work stress Recent life events such as losing your job, illness, an accident, or the death of someone close to you can trigger depression — particularly if you are already at risk. Many Australians have been affected by events such as the COVID-19 pandemic and natural disasters such as bushfires. Events like this can sometimes trigger symptoms of anxiety and depression. Internal factors Personal factors that may leave you more vulnerable to depression include: family history certain personality traits, such as perfectionism, low self-esteem and a tendency to worry drug and alcohol use can leave you more vulnerable to depression People with a family history of depression are at greater risk, possibly because of genetic factors. However not everyone who has a parent or sibling with depression will develop it themselves. Drug and alcohol use can be both the cause and a consequence of depression. Reducing alcohol consumption can be very helpful for people with depression. You can get help from the National Alcohol and Other Drug Hotline on 1800 250 015. Complex chemical changes occur in the body, particularly in the brain, when people have depression. Medical conditions can affect the way your brain regulates your moods. Many of the medicines used to treat depression work on these chemical aspects of depression.