Tiger will never be "back".
The dude's life no longer has the balance it had before. Tiger is a control freak. He is notorious for controlling the golf media (which fears him because he is well known for removing access if he doesn't like you), all of the people who have ever been close to him say he is very guarded and needs control at all times, etc.
His marital problems have led to a lack of control. His private life, which was once under tight lock & key, became an open book because he couldn't control the mainstream media the way he controls the sports media. It annoys him that he is no longer able to control his image.
His life in now completely out of balance. It used to be golf, bang some hoes, go home to his wife & kids, and more golf. Now, no more wife & kids. Now, supposedly no more hoes because he lives in tremendous fear of the gossip hounds and the TMZ's and the EXTRA's. And there is no question it has all effected his game, because his performance has never been the same since his wife took the 9-iron to his forehead and he smashed the Buick into the phone pole.
Unless Tiger wifes up his current GF, knocks her up, and goes back to drilling IHOP hostesses in his Escalade, he is done. He was a creature of routine, life balance, and control. He has none of that now.