If you were to marry Cersei, she's murder you in your sleep.
In the name of the Warrior, I charge you to be brave. In the name of the Father, I charge you to be just. In the name of the Mother, I charge you to defend the innocent. Arise, Brienne of Tarth... A knight of the Seven Kingdoms.
I will not kneel before some barefooted commoner and beg his forgiveness
As long as I'm better than anyone else, I suppose it doesn't matter