Uhhhh on Balo perhaps he's just had a rough upbringing where he felt like he didn't belong. Add in the racists and his home issues I'd say he's handled it all as well as one can.
I'm not so sure about that. His rough upbringing could still result in his inability to be comfortable in his own skin. Again, it's about reaction instead of proactive action in that case: you define yourself by others and what they seem to think, say, and do -- not by anything intrinsic to yourself. The challenge with that mode is that you exist in opposition to others, meaning your focus is external and not internal.
Now a lot of athletes use a chip-on-their-shoulder approach for motivation and to "prove others wrong" ... even if the fans are on your side. Psychological sports research shows a lot of sports figures use that as a crutch ... even to the extent of mentally fabricating a world of haters that really do not exist for them. And that is true regardless of skin color.
But I can't help but get a sense that Balotelli was always reacting to external forces and was never able to operate from within himself. The idiot racists everywhere made it more difficult for him than 99% of most athletes, to be sure. But without an ability to turn inward and not be purely motivated by the outward, he was always going to be lost.