It could be her conscience and her moral compass, telling her "This is evil and I must repudiate it!"
Equally, it could be that Theresa May's moral compass swings between "This make me popular in the Daily Mail!" or (occasionally and late) "Might I suffer consequences?"
Perhaps there are noises from The Hague, or of a Sanctions list, in consequence of actions that will never be tried as crimes in Brexitstan.