I am working on a post about the authorship of Wuthering Heights and I was pondering the behaviour and tragic decline of Branwell Bronte and it suddenly occurred to me that he may have been bipolar .I probably wouldn’t have considered the possibility of mental health problems within the Bronte family if I hadn’t just finished a post on Emily to address the question of her possible Asperger’s.
Its seems to me very possible Branwell had or developed a mental health problem that falls within the bipolar spectrum. Having lived with some one with a bipolar disorder, for years there was something about Branwells behaviour that niggled at some indefinable part of my mind .Then I began reviewing Branwell after I recently watched someone with bipolar slowly loose their moral compass and behave in increasingly uncharacteristic ways I saw many echo’s in Branwells final sad decline.
I don’t yet have research to back up this idea and may not pursue it but several aspects of Branwells life suggested the possibility
He was clearly extremely talented in many areas yet he also lacked the ability to maintain any interest for long enough to make a living ,he makes rapid progress then suddenly seems to loose interest or cant concentrate and apply himself .He often make grandiose claims and plans which he then looses interest in fulfilling.
He is affectionate and caring ,yet is sporadically capable of being selfish cruel and aggressive. He is aware of this and deeply upset by it but cant control it
Hes normally very gentle and protective of his sisters and father yet can be suddenly abusive and frightening .
He has sleep problems and delusions.He appears to be worse after some emotional upset or after sudden success.
He is by turns elated and depressed ,sometimes in rapid succession ,sometimes they changes can last days or weeks
Something I had not realised until recently ,each progressive episode seems to wear away at the suffers normal emotional state producing a gradual suppression of their normal self and an increasing intrusion of manic traits into their everyday lives.
Many aspects of his behaviour have been explained as results of abuse of alcohol and laudanum but there’s no evidence at all that he was using either of these when he makes his first “mistakes” and despite social drinking doesn’t seem to have lost control of his intake until the very last days of his life .The drug and alcohol abuse could have been a coping mechanism ,misunderstood by those around him who would have no idea of his complex mental health problems .
Thoughts to ponder by those more well versed on Branwell than myself
Hathaways of Haworth 
I thought this as well, it was as if he was self-medicating.
Yes ,I agree
I have had this thought as well when teaching manic depression and creativity in my Literature and Psychology class. See Kay Redfield Jamison Touched by Fire on creativity and manic depression.