The Once and Future King Book 3, Chapter 13
Guenever is twenty-two-older than Elaine, but not old enough to completely be an individual and have her bearings in the world yet. She does, however, have a vague sense of herself. So when Lancelot returns from Elaine, so completely ashamed of himself that he figures he may as well totally betray God, she goes to him without any debate. She always knew they would be together eventually.