In a tangle of alternate universes -- the TARDIS does go astray from time to time, just a little -- he finds war, chaos, destruction, entropy running wild.
But painful as these places are, one thought comforts him. It would have been different if I'd been here.
Somewhere. Somehow.
He never tries looking for Gallifrey in these alternative possibilities. If asked, he'd talk about intersecting timelines and the Blinovitch phenomenon and it being a really, really bad idea.
He chooses not to consider the possibility that he might be there, after all.
Or even that he might be the one to blame.
---