Without meaning to climb up on a high horse but...
I've been the victim of racial slurs pretty much all my life. I've had eggs thrown at me, glass bottles, rocks, drinks poured over my head.
It wasn't until I grew up and bulked up a bit that it thankfully stopped. And I'd like to think that I'm still psychologically healthy. If anything, dealing with the fact that not all of society copes very well with minorities and learning how to overcome that fact without turning to the same hatred that fuels it has made me more sane than I ever was.
The idea that coming from a place like Togo leaves players at a disadvantage is an interesting one, but having spent a large chunk of my gap year travelling that oft misunderstood continent, I can say that its biggest problem most definitely isn't modernity or advanced living, but how to spread that quality of life to the 90% of citizens who simply don't have it. Adebayor certainly doesn't lack examples or precedents - even devoutly religious ones - in his homeland who are blessed to be in the 10% of 'haves'. And yes, some of them are painfully corrupt and will tell you that 'God ordained it for me to have this wealth so why should I give it away?', but very very few actual believe what they're saying. The abundance of top class African footballers with far bigger names and far more spotlight than the two we're discussing, who've never displayed one shred of psychological imbalance leads me to think that Adebayor is the cause, rather than the effect, of his troubles.
Balotelli was privileged in the sense that he was fostered by relatively affluent parents to live in a relatively affluent country; yet he's still a sandwich and an egg salad short of a picnic.
It may sound harsh, but imho the reason is simply the sub-culture of skewed values that the business side of football sadly creates in so many players. The fallacious attitude that I somehow 'deserve' all of this money and attention for ultimately doing something that - when stacked up against pictures of refugees drowning - really doesn't make one iota of difference to the world.
People like Adebayor and Balotelli will have been living in this little bubble of privilege since a very young age. Without solid parenting and honest advisors (Adebayor certainly lacks both), it is all too easy for the cartoon hero to start believing the myth that the cartoon is actually real and that the money will last forever etc. To me, that is the point where psychological health begins to deteriorate into delusion.