Doctor Who: Doom of the Daleks
"Physician, heal thyself..."
At the start of his eighth incarnation the Doctor is dashing, exuberant and romantic, with a child-like wonder about the universe around him. While his thirst for adventure is infectious, the Doctor has an aura of danger about him that tends to warn potential companions away. Later in his life the Eighth Doctor becomes more apologetic and cynical, refusing to be involved with the Time War and limiting his efforts to help those affected by it.
The life of the Eighth Doctor is one of tragedy. In a series of events that would parallel his end, the Doctor was wounded in his previous incarnation and a doctor’s attempt to heal him resulted in his ‘death’ instead. The Seventh Doctor’s life was one of duty and responsibility; he was given great weapons by the Time Lords and used them against their (and the universe’s) enemies. With those missions completed, the Eighth Doctor could be born free of those responsibilities and travel the universe anew.
After an initial bout of amnesia the Eighth Doctor settles on a youthful, exuberant, romantic demeanour and is eager to see the universe with fresh eyes. For him the Time War is a thing of the past and his greatest enemies, the Daleks and the Master, are no longer a threat. Conversely, he also has a great deal of subconscious knowledge of the universe and realizes that the time stream is not set in stone; thus, he encourages people to make choices that he implicitly knows will make them better citizens of the universe. He also eagerly
invites new companions to share his discoveries of this new universe with him.
Unfortunately, the Time War is not over; it has been reignited into the Last Great Time War. The Eighth Doctor doesn’t realize this at first, as the initial sparks of the war didn’t affect him and the Master ‘died’ before revealing any clues. As the Eighth Doctor slowly learns of this deception he tries his best to avoid it, losing himself in his adventures with his companions. Unfortunately, his care-free, romantic nature becomes increasingly eclipsed with cynicism brought on by the re-ignition of the Time War and – by extension – his own role in the universe.
By the end of his life the Eighth Doctor shares many similarities with the end of his fifth incarnation; he finds his passive nature ill-equipped for an increasingly hostile universe. He watches painfully as the Daleks and the Time Lords tear all of time and space apart in an unnecessary conflict and his own guilt over having previously played such an important role in ending the war and falling short.
In the end, the Eighth Doctor was a cynical shell of his former self, refusing to believe he could positively affect the war as well as refusing to try.
-Copied from the source book