Depression and Anxieties – are they cousins or even more closely related?
Depressions and Anxieties can best be understood as ever diverging responses to the Whirlpool of Emotion.

Depressions are Floods and Anxieties are Volcanoes


Think about depression and anxieties as floods and volcanoes.
Depression and anxieties are both debilitating and destructive emotional conditions and they are related. Unproductive worrying is central to both, yet each will manifest differently as the flood and volcano metaphors attempt to demonstrate.
Anxieties can shoot off in a number of directions, exploding into the night full of nervous energy while depressions spread like a flood into every nook and cranny and so can smother all useful activity.
Another difference is that each impacts differently on sleep – go here.
Depression-Anxiety Spectrum
Where are you?
Setting you in Motion

TREATMENTS
Depression
Anxiety
Addictions
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Depression Therapy Online
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What is Depression
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Becoming Hopeful

This diagram is explained fully here.
It shows how emotions out of control (in the Whirlpool of Emotion) will inevitably cause a response as attempts are made to mitigate and control the emotion.
And these attempts assuming they fail are called mental illnesses.
In the centre I have put Anxieties as I see this as the cleanest response to a loss of emotional control where the flight or fight response is strong. And then on either side of Anxieties and merging into them (because the boundaries are never clear cut) lies Depression and Addictions.
When thinking of Depression and Anxieties, see them as related but as different responses to a situation of intolerable emotional distress.
Being related but different. – and thus requiring a response, that though also having common elements have at their core a different emphasis.