No, no, please don't cry. Not now. Anything but that. For most of her resignation speech outside Downing Street, Theresa May managed to keep it together.

Her diction was crisp, her delivery was brisk, her manner was forthright, almost valiant. She was all business, as usual.

For three winters and four summers, for over a thousand days in office, her troubled premiership has been marked by an absence of emotion that had something of the polar freeze about it. And then when the thaw finally came, it was terrible to behold.

Mrs May was overcome by tears as she spoke of her pride at having been PM, even though she admitted to having failed to deliver Brexit

'I will leave the job it has been the honour of my life to hold,' she said, and the first throb of emotion vibrated through her words like a plucked heartstring. She was the second female prime minister, but certainly not the last, she noted.

This was followed by another ominous ripple of anguish, a distress signal for what lay ahead.

For it was when she expressed her gratitude for being given the opportunity to 'serve the country I love' that her voice broke and the tears fell.

It was as if a glut of long-suppressed grief had somehow lodged in her throat, and for a moment her face wore an expression of cratered desolation.

I half expected her to throw back her head and ululate with despair for about half an hour, but no.

The Prime Minister announced her departure in an emotional statement on the steps of Downing Street today

Instead she pulled herself together, spun on her heel and vanished back inside No 10.

Perhaps she was furious that she had let her feelings show at this moment of all moments; the dusk of her career, the end of May.

I hope she had a stiff whisky and wasn't too hard on herself. For during her time as prime minister, she did her duty, she did her best under the most trying of circumstances and there is no dishonour in that, tears or no tears.

Perhaps many women might feel that by crying in public, even briefly, Mrs May let the side down. Certainly, it is not a good look.

It makes us all appear weak, with the underlying suggestion that women are unfit to cope with the rigours of high office.

Parallels will be drawn with Margaret Thatcher, the only other prime minister to shed a tear in public after being forced to resign.

Yet I would rather the honest tears of these exceptional women than the pompous, reputation burnishing orations that men seem to go in for when they exit the political stage.

Sometimes big girls do cry, and it is not always a weakness. To me, Mrs May's teary performance yesterday only reflected how invested she was in trying to clear up the Brexit mess.

One can only imagine the frustration, the anger, the regret and the utter exhaustion she has privately endured over these years.

And all of this made worse in a political arena dead set against compromise; in an atmosphere of vested interests and endless thwart, followed by bodge and gloat. Look at her.

She is a 62-year-old career politician whose only sin is a taste for wacky leopard print heels, and who has dedicated her life to public office.

Surely she must earn our respect and thanks for that.

Think of all those men who patronised this 'bloody difficult woman', on every side of the divide along the way. All those sneering Junckers and Tusks, Macrons and Corbyns, not to mention the unspeakables on her own side.

Her voice cracking, Mrs May said it had been the 'honour of my life' to be PM, and she hoped she would not be the last woman to lead the country

The premier walked back through the famous black door as the country digested the impending end of her premiership

'Unfortunately the Dancing Queen has met her Waterloo,' snickered Conservative backbencher Mark Francois after her resignation.

Mrs May may have had her faults and has certainly made her mistakes but my goodness, she is worth more than all of them put together.

Ironically, she looked better and seemed more energetic yesterday than she has done for a while.

Splashed by the flattering sunshine of a London summer morning, she wore a neatly tailored coral jacket and seemed almost optimistic.

Initially there was nothing funereal about her words or appearance; no gloom, no doom, none of her usual disappointed headmistress admonishments. She was lightly powdered and neatly groomed, every inch the vicar's virtuous daughter.

Philip May (pictured centre) looked as though he was suppressing an urge to comfort his wife as she made her speech. After her notorious coughing conference speech in 2017 he leapt on stage to embrace her at the end

The Mays left Downing Street via the back door after she made her dramatic departure announcement today

Poor Theresa. Despite all the good, she is going to be remembered as a PM who developed a knack of doing exactly the wrong thing at the right time; for losing her majority in the House of Commons; for presiding over a government that was anything but strong and stable and for failing to deliver Brexit. She must take some blame, yes, but not everything was her fault.

Her last frustration, perhaps the bitterest one of all, is that despite her fathomless, implacable resolution over these last few years, she will now also be remembered as a prime minister who cried in Downing Street when the hinge finally snapped.

What finally made her dissolve? Well, a woman and her tears. Such a very personal thing.

Who knows what goes on in the dark chambers of anyone's heart, but I don't think for a second that Mrs May was crying because she felt sorry for herself.

More likely they were tears of frustration and self-recrimination about the awful political impasse that her best efforts could not overcome.

Plus the sudden, ghastly dawning that all that beating against the tide, all that negotiating and talking and deal producing and compromising had been utterly in vain.

Everything came to nothing, and that is a sad legacy for any politician to contemplate. It is also a crying shame.