The 3-Headed Hydra: Anxiety, Depression, & Insomnia

These 3 disorders (Anxiety, depression, insomnia) on the surface appear to be separate and distinct mental disorders.
Anxiety is usually associated with some form of worry in the person's head.  Wikipedia describes anxiety as a  mental disorder that is the result of a difficult challenge for which the subject has insufficient coping skills.
Insomnia is the inability to fall asleep or stay asleep.  Insomnia is classified by the academic powers that be (aka Wikipedia) as a sleep disorder and not a mental disorder.
And depression in general is classified as a mood disorder (which itself is a subcategory of mental disorders) and there is generally a stigma associated with what appears on the surface to be a mental illness.

However, here's where the 3 are interconnected:  Anxiety triggers, leads to, or maybe even causes insomnia, which then creates the fertile ground necessary for depression to take hold.  Once the person enters a depressed state it allows the anxiety and insomnia to grow like weeds.  All three feed on each other.  However, resolving the anxiety disorder (by positive self talk and Cognitive Behaviour Therapy) does not fix the other problems (insomnia and depression).  Depression, once it takes hold, is the toughest monster to slay. People who suffer from chronic depression does lead me to wonder whether the monster ever did  go away, or actually has been there all along, but just sleeping.

Depression is the hardest to fix, and requires a combination of positive self talk (CBT), lifestyle changes like eating a balanced meal and exercising consistently and a support system.  Also, the person suffering from depression must force themselves to be preoccupied with some work or task throughout the better part of the day.   When the mind if focused on the task or work at hand, that means it is not focused on the depression.  It is not fed and that is key.   Having a support network of people helps to stick to the lifestyle changes and positive self talk.
Insomnia is the easiest to fix, and usually a trip to the doctor for some sleep medication, along with some good sleep hygeine usually fixes insomnia.