Kurt didn't suffer from mental illness

This is incorrect. I actually did a paper on him in college, he suffered from Bipolar Disorder and was subject to large mood swings. His family tried to get him treatment, but he would self-medicate with other drugs frequently. It's believed that when he committed suicide he was on the "depressive" side of the swing.

From his cousin who is a registered nurse and was trying to help him with his treatment:

Strong evidence connecting Kurt Cobain and manic depression comes from an interview with Kurt's cousin, Bev Cobain. This interview contains the following question and answer:

Q: Did Kurt have other mental health problems besides general depression?

A: Kurt was diagnosed at a young age with Attention Deficit Disorder [ADD], then later with bipolar disorder [also known as manic-depression]. Bipolar illness has the same characteristics as major clinical depression, but with mood swings, which present as rage, euphoria, high energy, irritability, distractibility, overconfidence, and other symptoms. As Kurt undoubtedly knew, bipolar illness can be very difficult to manage, and the correct diagnosis is crucial. Unfortunately for Kurt, compliance with the appropriate treatment is also a critical factor.

Bev Cobain is a registered nurse with a background working in mental health. This background, combined with the tragic loss of Kurt, have led her to become an expert and energetic activist for suicide prevention. Her comments that Kurt was actually diagnosed provide strong evidence for linking Kurt Cobain and manic depression.

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