When she left the care of the gray-skinned people she was fully at peace with herself. But peace with herself was not enough. She saw the suffering her own people caused as their military rampaged through the galaxy, and longed for them to return to the true meaning of their name. Peacekeepers. Not Warmongers.
The violent excesses of the Peacekeepers were caused by fear, she knew. Fear of other races, fear of war. Particularly fear of the Scarrans. If only a lasting solid peace could be brought about between the Sebaceans and the Scarrans, the Sebaceans could give up being conquerors and be protectors once again.
A person with such a philosophy couldn't rise within the ranks of the violent, war-dominated Peacekeepers without an ace up her sleeve. The heppel oil gland would kill her young; she'd be lucky to get 70 cycles in a life that should have been 250. But she would make that sacrifice, for her people, for peace.
As time went on and she climbed the ranks, the violence wore off on her, corrupting her. She longed to return to her pale benefactors and accept the joy, the ease that they could give her. And if the stakes hadn't been so high, she would have. But she was desperate. Forces were arrayed against her, trying to promote the war. Scorpius was continually agitating for total war against the Scarrans, and despite his despised half-breed upbringing, the fact that he knew the Scarrans so well because of that upbringing led the High Command to take him seriously. She had to take him down, by any means necessary, or there would never be peace in the galaxy.
Sometimes Mele-on would remember how she had felt in the care of the Nebari, and who she had been, and when she compared it to who she was now and what she had done for her cause she wanted to weep. But it was necessary. The Peacekeepers would never again find their moral center if she were too moral to bring them a peace to keep.