People tend to be confused when they see insomnia as one of the symptoms of depression, and depression as one of the symptoms of insomnia. The simple link between the two disorders is that both go hand in hand. Insomnia simply refers to the inability to fall asleep or stay asleep in the night. Most times, this condition might linger until it becomes chronic. Chronic insomnia is very dangerous to one's health and daily performance. However, the simple relationship between depression and insomnia is due to anxiety.
When an individual starts having frequent difficulty in having a good length of sleep, he begins to be anxious about the sudden reality, if this persists the anxiety grows stronger, and anxiety has been confirmed to be one of the causes of depression. When depression comes in due to insomnia, it will further worsen the condition as depression itself can lead to insomnia.