I think one aspect not mentioned is how Cobb became so famous at such a young age and what effect that would have had on him - or anyone.
At age 20, he won his first batting title and was the brightest young star of a sport experiencing a huge rise in popularity. He was well paid and received special treatment from his manager right from the start of his career. Basically, he had a lot of the same issues that many young, famous athletes have today when given piles of money and fame at a very young age.
My favorite Cobb:
1909 Cobb E95.jpg