user5315: Mental illness is not uncommon in modern society, from mild to severe illness. Depression, (generalized) anxiety disorder, panic disorder and schizophrenia, to name a few. Do people with (long-term) mental illness are "destined" to be reborn in one of lower realms or they're seen just illnesses rather than unwholesome states of mind? What is the cause of mental illness from Dhamma point of view?

user43: What is the cause of mental illness from Dhamma point of view? Well, it's attachment of course. Attachment to false, harmful concepts. Attachment to harmful sources of emotional energy. Attachment to old experiences. Even attachment to traumas.
Attachment makes us stuck, rigid, dysfunctional. "Klesha"s are mental and emotional obscurations that we generate through our attachment. Kleshas are like clouds that distort our perception of reality.
And why do we attach? Because we want to avoid pain. Physical pain, mental pain, emotional pain. We think that by holding on to one side, we can escape the pain associated with the other side. But that's an illusion, the more we avoid pain the more frightful and painful we make it. And that fear of pain becomes gasoline that feeds the engine of mental illness. 
So from this standpoint the way to mental health is through letting go of attachments, letting go of fear of pain, letting go of extreme polarization, towards integration and acceptance of the opposites. Essentially letting go of false harmful concepts of the world and self, and the emotions associated with those concepts. This is why study of Emptiness is a key, because it leads to deconstruction of rigid concepts.
From the perspective of Enlightenment, we are all mentally ill in some degree. Mental illness is just a more blatant case of samsaric thinking, and Dharma is medicine for the mind.

5315: <p>Mental illness is not uncommon in modern society, from mild to severe illness. Depression, (generalized) anxiety disorder, panic disorder and schizophrenia, to name a few. Do people with (long-term) mental illness are "destined" to be reborn in one of lower realms or they're seen just illnesses rather than unwholesome states of mind? What is the cause of mental illness from Dhamma point of view?</p>
 43: <p>What is the cause of mental illness from Dhamma point of view? Well, it's attachment of course. Attachment to false, harmful concepts. Attachment to harmful sources of emotional energy. Attachment to old experiences. Even attachment to traumas.</p>

<p>Attachment makes us stuck, rigid, dysfunctional. "Klesha"s are mental and emotional obscurations that we generate through our attachment. Kleshas are like clouds that distort our perception of reality.</p>

<p>And why do we attach? Because we want to avoid pain. Physical pain, mental pain, emotional pain. We think that by holding on to one side, we can escape the pain associated with the other side. But that's an illusion, the more we avoid pain the more frightful and painful we make it. And that fear of pain becomes gasoline that feeds the engine of mental illness. </p>

<p>So from this standpoint the way to mental health is through letting go of attachments, letting go of fear of pain, letting go of extreme polarization, towards integration and acceptance of the opposites. Essentially letting go of false harmful concepts of the world and self, and the emotions associated with those concepts. This is why study of Emptiness is a key, because it leads to deconstruction of rigid concepts.</p>

<p>From the perspective of Enlightenment, we are all mentally ill in some degree. Mental illness is just a more blatant case of samsaric thinking, and Dharma is medicine for the mind.</p>
