Angela Merkel came to London and told David Cameron that Germany will no renegotiate Britain's membership terms and that is Britain wants to leave so be it. All the excuses and delays justified by the Prime Minister regarding a renegotiation of Britain's membership are no longer valid.
One possible answer and perhaps the answer is that David Cameron does not have the faintest intention of changing the status quo with Europe and that all the promises made have been merely a smoke screen to deter Conservatives from joining other political forces including UKIP under Nigel Farage's leadership. This is no longer about the Conservative/Liberal Democrat Coalition. This is about the fact that the leader of the most important country in Western Europe has said NO.