There is no "underlying cause" that can definitely pointed to, that's just hubris. You can't know that if those things didn't happen he wouldn't have still beco

There is no "underlying cause" that can definitely pointed to, that's just hubris. You can't know that if those things didn't happen he wouldn't have still become someone who would drink themselves to death, or that if something else happened, such as becoming devoutly religious, he might have been able to avoid it.