However, one's own attitudes about depression can cause a person to go without medicated for years, even for a lifetime. Many depressed people attribute their sadness directly to their life situation and think nothing more of it. Depression is completely different. There are distinct symptoms. The symptoms of depression can vary depending on the person's personality and past experience however, there are common symptoms to look for.
Social isolation is probably the most common symptom for depression.
Other symptoms are lack of motivation, insomnia, loss of appetite, irritability and anxiety. Another thing to look for is changes in personality. The person stops doing activities they normally enjoy. They may sleep for hours every day, miss appointments, be late for work, or feel tired all the time. Those who want to help might ask the person how they are feeling and perhaps point out that they haven't been themselves lately.