Under the union jack bunting of chilly street parties or next to the children’s bouncy castles at the village jubilee fetes, Conservative MPs have been quietly taking the mood of their constituents before returning for a week of bloodletting in Westminster.

“I‘m getting people coming up to me and greeting me with that smile and the tilt of the head that’s usually reserved when your labrador puppy has just been run over,” one senior MP said. “It is deeply uncomfortable.”

Though few have been directly confronted with angry constituents demanding they oust the prime minister, most admit there is an awkwardness about the encounters.

“I don’t think that anyone wants to spoil the weekend but I have been asked by some members of my association if I have considered sending a letter,” one MP said. “This is new territory, it is very serious. It’s like denouncing family.”

Several said the criticism was coming more in sorrow than in anger – one recalling a Conservative-voting couple who told them that they had 130 years of membership of the party between them. “They said they cannot vote for us again with any self-respect while Boris Johnson is in charge.”

Even at the moment of national celebration, Johnson’s situation has intruded unhappily. The prime minister was booed walking up the steps to St Paul’s – a moment described as “embarrassing” and “humiliating” by his colleagues – and was the butt of jokes from the comedian Lee Mack opening the jubilee concert.

Some of those supporters of Johnson say those jokes by Mack or Stephen Fry may help the prime minister – “It shows his critics are the luvvies class,” one said. But the booing is far harder to ignore.

“These are ardent royalists who will have got there at four in the morning, not vegetarian Guardian readers,” one MP said. “These are the friends of the community hospital, your town councillors, the backbone of Britain.

“A Tory prime minister would usually expect to get some sort of bounce out of a jubilee weekend. But I think, strangely, it actually reminded us of the prime minister’s deficiencies.

“We’ve been talking about duty. We’ve been talking about service. We’ve been talking about subjecting the person or the self to the greater good. All of these things are an anathema to the prime minister.”

But even among the staunchest of Johnson’s critics, they admit there is no consensus about his replacement – and that their voters have very little enthusiasm for an alternative.

The overwhelming sense that MPs report is a general sense of ennui and frustration from the public. “We have banned political talk all weekend,” one MP said.

Many said the emails they had been receiving about Partygate had dried up – though several said that was because they believe the public had decided what they thought of Johnson long before Sue Gray’s report.

“The public is truly fed up – many blame the PM, some blame all politicians, others blame the media’s ‘obsession’,” one said. “I’ve had 30 emails since the Gray report – far less than normal. Most of those emailed for the first time around January but have stopped mailing now. It is definitely true trust of politics and in politicians is very low.”

Some of the “red wall” Tories who are deeply loyal to Johnson feel particularly aggrieved at the plot to oust him – and warn it will lead to further party divisions.

“There’s an assumption among some colleagues that if the greatest election-winning PM in a generation goes, MPs like me will suck it up and unite behind a new leader. They are wrong,” the 2019 intake MP said.

One veteran MP said he was very worried the party would end up looking more and more divided under a new leader, because of the uncertainty of a race.

If it comes, it is likely to include candidates from all wings of the party – including Jeremy Hunt, Rishi Sunak, Sajid Javid, Liz Truss, Penny Mordaunt, Tom Tugendhat and even outsiders such as Tobias Ellwood or Mark Harper.

All of those candidates would alienate certain Tory factions – not to mention voters – said the MP. “The risk is that you defenestrate the prime minister, and then you end up with a leader that you don’t like – which is perfectly possible,” the MP said.

“It is actually very likely, because there’s no obvious successor, then you’re going to have a very close run campaign with a variety of different candidates.”

Most MPs – who are mulling over the prospect of a divided parliamentary party with horror – have spent the weekend trying to turn conversations back to local projects or emphasising their own credentials as decent public servants.

“All any of us can do is our best, trying to lead by example and sticking up for integrity,” one former minister said. “Of course Theresa May did that, and it wasn’t enough in the end, but it’s the only way most of us can live with ourselves.”