Then again you shouldn't have to still ensure you do what you decided to do 3 years ago.
The main issue with the referendum was that it should have asked for some type of enforced majority (eg 60%). But that would also have been hard to sell, and Cameron wanted to be PM, so to hell with you plebs
The main issue with the referendum is that Cameron didn't expect to lose so it said nothing about what type of Brexit we were actually voting on or how that was to be decided.
May could've got Brexit (or at least this 1st stage) done fairly quickly if she'd gone for a Norway-style deal but her obsession with ending free movement prevented that.
Now we're supposed to accept a deal that will rip up environmental standards, workers rights etc.