From Stargate: The Ark of Truth
Nothing I have done since turning against the goa'uld will make up for the atrocities I once committed in their name. Somewhere deep inside you you knew it was wrong, a voice you did not recognize screamed for you to stop. You saw no way out, it was the way things were, they could not be changed. You're trying to convince yourself the people you're hurting deserved it. You became numb to their pain and suffering, you learned to shut out the voice speaking against it.
There's always a choice.
Indeed there is.