It's sad and frightening to think this might be a man who sees himself as being in the twilight of his life - the last ember of Gallifrey, burning down.

Good point about companion death. For the Doctor, losing Rose and her (and his, in a way) family to the other universe must be parallel to losing his own family and his people to the "other universe" of death; it's just got that bittersweet addition that she's still alive and she's fine, like knowing for a fact someone's in heaven.