IIRC May was opposed to Brexit. AFAICT she's been trying to get the best deal Britain can get, it's just that all the brexiteers don't get that what they want is not what they are going to get if they go with their own 'drop everything EU' plan. Britain's too connected and dependent on the continent, and the Commonwealth is not going to bail them out.
And sure, a drop everything EU Brexit is also going to hurt the European Union, but not nearly as much.
And sure, a drop everything EU Brexit is also going to hurt the European Union, but not nearly as much.