Conversation so far:
Did John ever possess ecstasy?
subsequently found to be in possession of one ecstasy tablet.
Was he arrested?
Johns was arrested.
Did he regularly take ecstacy?
Johns initially claimed that an unknown person had pushed the tablet into his pocket.
Did he take the drugs for a reason?
he later forgot to remove before leaving the crowded venue.
Did he ever go on TV and state why he took drugs?
On 30 August, Johns revealed, live on the Footy Show, that he had regularly taken ecstasy throughout his playing career.
Are there any other interesting aspects about this article?
He claimed he had suffered from depression and bipolar disorder and the drugs helped him in dealing with the high level of psychological 'pressure.

Question: why did he suffer from these disorders?
Self-contained rewrite: why did Andrew Johns suffer from depression and bipolar disorder?