Because she promised a submarine made of cheese, and delivered a submarine made of cheese, and the people who demanded a submarine made of cheese are mad that i

Because she promised a submarine made of cheese, and delivered a submarine made of cheese, and the people who demanded a submarine made of cheese are mad that it doesn't taste good enough or dive deep enough. There is no such thing as a favorable brexit deal. Britain is already in the most favorable position possible with regards to EU relations: they have all of the benefits of EU membership, but with a special deal that means they're exempted from some of the membership dues, and they can have their own immigration policy and their own money. Britain has a more beneficial position in the EU than any other country in the world, in or out. There is absolutely no way that the EU is going to let them leave and keep most of the benefits of membership. The hardliners want to get everything and give nothing, and surprise surprise, the EU wasn't going to let them have everything in exchange for nothing, so the hardliners hate it, and everybody else hates it because it was a stupid idea in the first place.