It’s been a busy few days for the prime minister. The weekend in Japan for the G20 summit and then a couple of days in Brussels while the other EU countries divvied up the top jobs between them. But everywhere Theresa May went she was treated with polite indifference. A ghost at the wedding. The louder she yells for some kind of legacy by which she can be remembered – even a photo opportunity with a minor dignitary would do – the less she is heard. So rapidly is she being airbrushed out of her life, not even she is entirely certain she really exists.

There wasn’t even a murmur as May shuffled into a half-empty chamber – most Tory MPs were off getting their picture taken with Boris Johnson: it would always be nice to have a record of his future betrayal for the scrapbook – and took her seat alongside the chancellor. One of the few members of the cabinet still capable of looking her in the eye. It’s curious that the man who is among the most loyal is the one with most reason not to trust her. Had May won the 2017 general election Philip Hammond would have been out of a job two years ago. Perhaps he takes pleasure in watching her decline at first hand. He’ll outlast her for sure. If only by a matter of hours.

In recent weeks Jeremy Corbyn has steered clear of mentioning Brexit at prime minister’s questions. Largely because Labour’s own Brexit position can’t survive much scrutiny. But with Boris Johnson and Jeremy Hunt trying to outcompete with one another to prove who is the most clinically insane, not even the Labour leader could pass up the opportunity of an open goal.

Corbyn kept it simple. The chancellor had said a no-deal Brexit would cost the country £90bn. Johnson had claimed that was confected hysteria. Which of them was right? Something inside May snapped. After years of speaking in semi-detached, meaningless binary, the Maybot finally got in touch with her anger. But it had been repressed so long that it came out hopelessly misdirected.

I had a deal, she snarled. It might have been a crap deal, but it was her deal. And if only Labour had voted for it then the UK would already have left the EU by now and she could have been prime minister for ever and ever. There was a moment’s silence after this. No one had seen May come close to losing control in the Commons and needed time to process the madness.

“Er... fine,” said Corbyn. But could she still answer his original question? No. She couldn’t. “I HAD A DEAL,” she yelled, spit flecking around her mouth. “I HAD A DEAL AND IF LABOUR HAD VOTED FOR IT I WOULD STILL BE QUEEN.” The Labour leader tried to talk her down. This was the way parliament worked. The government governed and the opposition opposed. So the reason her deal had not got through three times wasn’t just because it was a bit rubbish – if it had been any good Labour might have given it the OK – but because her own backbenchers had voted against it.

This still didn’t compute with the Maybot. No matter how clearly it was spelled out to her, she couldn’t get her head around the fact it had been her own party that had let her down. The level of denial was still just too great. Corbyn even mentioned the fact that Labour had put forward a motion to take no deal off the table that she had voted against, but this only provoked further confusion. “You’re all mouth and trousers,” May said. She couldn’t even get that right. Control, alt, delete.

It was a raging against the dying of the light. Shortly after she had announced her resignation, she had appeared to find some kind of calm. As if there was a relief in the inevitable having finally happened. Some weeks later, she has moved on to the second stage of grief and, as she stayed on after PMQs to give a statement on the G20 summit and the European council in which the full futility of her existence was laid bare, her anger became steadily more focused.

So what if there was no one to hear her primal scream? May could still enjoy her revenge. Fed up with listening to Bill Cash droning on about how the only good Jerry was a dead Jerry and pressed again to endorse Johnson’s no deal, she pointedly declined. She’d make her feelings known from the backbenches in due course. She knew where the bodies were buried and there would be blood. The only real question was whose it would be.