How has it come to this? Theresa May and her husband, Philip, have long been friends of mine and I have in the past admired her sense of duty and commitment to her party and her country. So it grieves me that her stubborn choices have left both in peril.

At a time when our politics needs statesmanship, not brinkmanship, when our divided people need time to heal and come back together, and when our country needs honest leadership rooted in reality not ideology, Mrs May has embraced division. Rather than providing the calm, compassionate and unifying leadership we so desperately needed after a divisive EU referendum campaign, she rushed to own Brexit. She has clung to power in the process, but she is letting us all down.

The roots of the current crisis are deep and reflect decades of neglect of our political system. There is truth in the saying that, in a democracy, people get the government they deserve. It should be a wake-up call to us all that our country’s future is being so fundamentally shaped by political party memberships that have narrowed to the extremes.

However, it is Mrs May who must take responsibility for the current crisis. It is the result of her government’s failure to secure a satisfactory outcome to honour the 2016 referendum result. Any government would have struggled to meet Vote Leave’s fake promises, but her choices have gone against all common sense.

She took it upon herself to interpret a referendum on a complex issue, setting out “red lines” without reference to the people who voted or to those elected to represent them in parliament. She undermined trust by trying, and failing, to deny parliament a meaningful vote in the courts. She triggered article 50 without a realistic plan. She failed to hear the message implicit in the 2017 general election result: that the country didn’t want Brexit at all costs. She set out to reach a compromise that Brexiters and Remainers alike were always going to view as the worst of both worlds. And she has used bullying and fear to try to force it through parliament. These were all her choices.

Mrs May's words in Downing Street were the most irresponsible of any prime minister in my lifetime

Mrs May’s statement in Downing Street last Wednesday, in which she pitched our country’s people against their parliament, was a new low: the most irresponsible words I can remember any prime minister uttering in my lifetime. And it is part of a pattern in which Mrs May has picked up the baton from Ukip in poisoning our political discourse and deliberately undermining public faith in the institutions that form the very fabric of our society.

In politics, and in the media, our judges have been condemned as “enemies of the people”, the governor of the Bank of England, Mark Carney, was abused as a corrupt liar for suggesting Brexit might not be good for our economy, while academics are told that the UK no longer needs “experts”.

Our toxic political discourse has likely fuelled the rise in hate crime. The murder of Jo Cox in 2016 should have been a warning. But one colleague, Anna Soubry, is this weekend unable to return to her home following death threats. Another, Lloyd Russell-Moyle, was accosted on the street by a man shouting that MPs were traitors and who then tried to assault him. Three bystanders had to prise the man off. Our brave and principled former attorney general, Dominic Grieve, has been threatened with death by people who don’t like the fact that he wants to prevent a no-deal Brexit.

I have also experienced abuse and intimidation after I resigned from the government to campaign for a final-say referendum on Brexit last summer. MPs are now being urged to take taxis and travel in groups because of the threat to their safety. And the Speaker of the Commons, John Bercow, himself the target of public attacks, has had to intervene to remind MPs that, whatever their position on Brexit, they are not traitors to their nation.

The BBC, too, has done itself harm by pursuing a flawed approach to achieving “balance” in its coverage of Brexit. The views of Nobel prize-winning economists on the risks of Brexit are simply not of equivalent merit to those of Nigel Farage.

It doesn’t need to be this way. We need wise, responsible leadership at this time of self-inflicted crisis. And it is also clear that we need to go back to the people to seek what I call, as a doctor, “informed consent” for what happens next, in a new referendum.

A no-deal exit would ensure that she goes down in infamy... she has made a bad situation worse

Mrs May should ensure that the UK has the time and the space to do this in a properly considered way – either by seeking a long extension of article 50 or by taking back control and revoking it altogether.

I know that Mrs May cares about her legacy. I urge her to realise that delivering Brexit, on whatever terms, will not secure a good one. Indeed, a no-deal exit would ensure that she goes down in infamy. Our electorate has not been united on much in the past two-and-a-half years, but a poll recently showed that more than 90% of voters think the situation we now find ourselves in has become a national humiliation.

Mrs May has failed to implement the 2016 referendum result. Perhaps anyone would have struggled. But she has made a bad situation worse and her mandate has now expired. The majority of both Remainers and Leavers does not believe that Brexit, on Mrs May’s terms, is a satisfactory outcome – and public opinion also seems to have changed.

The argument that people want to “get on with it” so the government can focus on other things is fatally undermined by the fact that Mrs May’s deal, if it were ever passed, would not be the end of the matter. It would lead to years, possibly decades, of more tortuous negotiations with the EU on our future relationship.

Whatever happens next with Brexit, the damage that has been done to our institutions will take a long time to heal. All of us with any decency in politics, and in our country, must work to that end.

Mrs May once famously declared that nothing had changed. I plead with my friend the prime minister to realise that, when it comes to Brexit, everything has changed. The people must have the final say.

• Dr Phillip Lee is the Conservative MP for Bracknell