from the Guardian's Jonathan Lis

Don't buy the Brexit hype: it's a border in the Irish Sea or the customs union

which begins

Donald Tusk's clear rejection of Theresa May's Chequers plan at the Salzburg summit yesterday should not come as a surprise. The most important lesson of the Brexit negotiation is that it is not a negotiation, and never has been. Blessed with superior size, wealth and power, the EU has been able to dictate the framework and substance of the talks, and has refused any deviation from its red lines.

and finishes:

The [UK] government has never understood the Brexit process and therefore has always botched it. It expects the EU to treat the UK both as an equally powerful third country, and as a member state still deserving the EU's protection. It is neither. And so in a battle of red lines, the UK will lose. That is the most brutal lesson of all.

and again The Guardian - Rafael Behr

The EU couldn't help May at Salzburg because she's seeking the impossible

Ultimately the EU cannot give May what she really needs, which is a Brexit model that will simultaneously satisfy the whole Tory party and win support from a majority in the Commons, without inflicting harm on the country. They cannot give her that because it doesn't exist, never did, never will.

At politics.co.uk, Ian Dunt applies his usual critical analysis:

Brexit: Brussels just got serious

But today's events suggest something has changed. You could see by May's expressions, which were even more strained than normal, that she had been taken by surprise. Things had fallen apart.

In reality, nothing has changed - Chequers was never going to happen this morning and tonight it remains something that is never going to happen - but it is extremely significant that Brussels has changed its attitude.

Perhaps they grew tired of Britain presenting Chequers as a take-it-or-leave-it proposition. After all, May's shock suggests she might have really believed it would fly. We must pray that is not the case because it would suggest that she is so detached from reality that she cannot functionally perform the role of prime minister. [Emphasis added by me]

From the pieces I quote, you will realise I believe that for 27 months there is an inevitablity about the position we have reached.