When I woke up at 5.25am on Friday, I checked my phone and saw the front page of The Sun. I actually exclaimed: “F*****g hell”, as opposed to “F*****g hopeless.” I was due on air on Good Morning Britain an hour later with Jacqui Smith. We were both staying in the same hotel so I texted her [contrary to popular rumour we did not share a room!] the link.

When we got to GMB just before 6am the programme editor told us that for legal reasons and Ofcom rules they couldn’t show the front page and couldn’t detail the allegation. Yet, we were still expected to comment on it! Kate Garraway referred to it as an allegation about his private life. It was, of course, much more than that. Had it just been an affair between a married cabinet minister and a woman who wasn’t his wife, Hancock would have survived. But it wasn’t and he couldn’t.

I said to Jacqui that his departure would depend on one thing. In fact, in the end it depended on two.

Firstly, the question he and his colleagues would have to answer was this: did the affair start before his ladyfriend was appointed a non executive director of the NHS or after. If it was before, then there was a clear conflict of interest. That is a resigning matter on its own.

Secondly, the fact that he was breaking all sorts of social distancing rules, and kissing and hugging when he was telling families that they could not hug each other or have any contact with dying relatives, meant that he was open to accusations of rank hypocrisy. He wasn’t just any old minister, he was the minister who drew up the rules and was enthusiastic in enforcing them. His comments on Professor Neil Ferguson’s resignation to Kay Burley were played hour after hour on Sky News throughout yesterday.

As someone who has watched these situations play out time after time over the last forty years, I felt that his departure from government was pretty inevitable.

Boris Johnson was damned if he did sack him, and damned if he didn’t. It is admirable in some ways for a prime minister to be display loyalty to his ministers and not hand the media a scalp on a plate. If you sack someone too early it sends a very bad message to your ministers and to your MPs. But if you don’t and issue a message of support and declare the matter closed, you’d better be sure it really is.

The trouble for Boris Johnson is that if he had sacked him immediately, he too would have been accused of rank hypocrisy given his, er, questionable private life behaviour and morals.

In addition, when a scandal breaks on a Friday you can be pretty sure there will be some fuel to add to the fire in the Sunday newspapers. It may be that Matt Hancock got a whiff of this earlier today and reached the conclusion that his position was now untenable. Either that, or close political friends like George Osborne may have made him realise that he couldn’t survive. When you’re in the eye of the storm you often lose perspective and think that you can ride it out. All my political instincts told me yesterday and today that he would have to go, and go within the next week, and I said so on today’s ‘For the Many’ podcast. Five hours after the episode dropped, it was already out of date and he had gone.

Ministers serve both at the pleasure of the Prime Minster and of the Conservative Parliamentary Party. When a minister is in trouble you often see Tory MPs circle the wagons and fan out on the media to protect a senior member of their tribe. Not here. Both yesterday and today Tory MPs were notably absent. And then this morning the North Norfolk MP Duncan Baker called on him to go. The dam started to leak water. I had three ministers text me this afternoon saying there was no support for him in the parliamentary party. It was then that I knew he would have to go.

Ninety minutes later, I heard the news of Hancock’s resignation from my friend Keith Simpson who phoned me on the way back home from the Felixstowe Literary Festival. I had the Wales v Denmark match on the radio and I hadn’t checked my phone when I got into the car. When I finished the call I reflected both on the political consequences, but also the human tragedy. I’m not a close friend of Matt Hancock’s, but I know him and I like him. I’ve always enjoyed interviewing him and he’s always been very responsive. So on a human level I feel very sorry for him. Obviously, he’s brought it upon himself and his family, and he will know only too well what he’s done. Two families and six children’s lives have been turned upside down. He will feel a sense of personal humiliation and will no doubt be aware of the some the internet memes which have been circulating since Friday morning. So yes, I do feel for both him and his family, but he has done the right thing in quitting.

I thought that the Prime Minister would appoint a replacement who had some experience and knowledge of the handling of the Covid crisis. Jeremy Hunt was being speculated upon but a) I doubt whether he’d have said yes, and b) Boris Johnson would have been reincarnating a leadership rival. Michael Gove was an option as he has coordinated the government’s Covid response from the Cabinet Office. He would have been a radical choice, but it may be that there are other plans for Gove’s future. I would have gone for Nadhim Zahawi, given his superb performance in the vaccine rollout.

In the end Boris Johnson plumped for Sajid Javid, a good communicator and a safe pair of hands. And Boris has always felt he owed him over the manner of his departure from government 16 months ago. The downside was that it allowed Dominic Cummings to blame it all on the Prime Minister’s wife. This mantra is now getting a little tired.

Today was a sad day for many people, a sad one for the reputation of the Conservative government and party, and a tragic one for two families.

In government when a minister resigns it’s very much a case of ‘The King is dead, long live the King’. The ex-minister disappears into obscurity to lick his wounds and think of a path back to prominence, while the innocent victims of his actions wonder how their lives can ever be the same again. And the awful truth is that they can’t.

Human fallibilities always have consequences. Families up and down the country experience the consequences of adultery every day of the week. A politician’s adultery, though, is played out before the gaze of the public. And it’s never very edifying.

A final word on the politics of this. Boris Johnson's government is on the precipice of gaining a reputation for being both incompetent and a bit scandal ridden. The last Conservative government that acquired that reputation was thrown out of power in 1997 in a particularly unceremonious way. The Conservatives cannot rely on having an anonymous opposition and an anonymous opposition leader for ever. By the way, where exactly is Sir Keir Starmer, apart from rearranging the deck chairs in his office? 

When Boris Johnson's reshuffle eventually materialises he needs to promote people who exude competence and the ability to explain government policy on the media. Because tonight many Conservatives feel utterly bereft and wonder how long they can keep supporting a government which lets them down at every turn. 

Some are wondering whether, after not quite two years in power, we have already experienced 'peak Johnson'.