Blame for this pickle lies at many doors.
I do feel however that if many had accepted the result and aimed for the best exit possible rather than continually scuppering and sabotaging and delaying hoping that it would go away and we'd simply give up, then the pill would be easier to swallow.
But the fundamental problem is "what is the best exit possible"? Even if you only asked the 17.4m Leave voters you'd get 10m different interpretations at least. The issue goes all the way back to the Leave campaign actively deciding not to pursue a singular vision of Leave prior to the vote in the hope that they could win the vote then "it'd be alright on the night".