I think the General Election fiasco has played a bit part in why we are where we are today. May correctly identified that the majority she inherited from Cameron was not big enough given that there would be a large body of MP's who would try and frustrate Brexit and undermine the Government's position. On the face of it, it made absolute sense to try and get a bigger majority given the opinion polls were showing 20+ percentage point leads. But what followed was probably the worst general election campaign ever with May exposed as a wooden performer. It resulted in her losing even the small majority she previously had.
After that May was severely weakened and the Government was undermined at every turn with remainers like Blair and Clegg rushing to Brussels urging the EU to offer harsh terms so that we might decide to have a second referendum and overturn the first one. Even part of the Cabinet joined in the act, repeatedly saying how bad no-deal would be. Phillip Hammond even refused to release the money required by Government departments to prepare for it. It was reported at the time of the General Election that May was about to sack Hammond. Now she was too weak to do so. The result has been a shambles. The EU (rightly) concluded that we wouldn't leave without a deal and had therefore no incentive to offer a good one. Rather they could offer a bad deal in the hope the decision could be reversed or at the very worst let us leave but on vassal nation terms.